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Apache Juneau (incubating) 6.2.1-incubating-SNAPSHOT API

Apache Juneau Overview

See: Description

Package Description
Base toolkit for serializers, parsers, and bean contexts
General bean annotations
CSV serialization and parsing support
Data transfer objects
ATOM Data Transfer Objects
Cognos Data Transfer Objects
HTML5 Data Transfer Objects
JSON-Schema Data Transfer Objects
Swagger Data Transfer Objects
Encoder API
HTML serialization and parsing support
HTML annotations
RFC2616 HTTP Headers
INI file support
Internal classes not meant for external use
Jena-based RDF serialization and parsing support
RDF annotations
Java-serialized-object support
JSON serialization and parsing support
JSON annotations
Juneau Cloud Microservice API
Predefined Microservice Resources
JSON serialization and parsing support
Parser API
Plain-text serialization and parsing support
Remoteable interface proxies
REST Servlet API
REST servlet annotations
REST client API
Predefined REST response converters
JAX-RS / Wink integration components
JAX-RS / Wink integration components with RDF support
RET servlet API with Jena components
Various REST interface label classes
Predefined Matchers
Remoteable service API
HTTP Response handlers
Predefined SVL variables  
Serializer API
SOAP/XML serialization and parsing support
Simple Variable Language
Simple Variable Language - Predefined variables
Transform API
Predefined Transform implementations
UON notation serialization and parsing support
URL encoding serialization and parsing support
URL-Encoding annotations
Utility classes
XML serialization and parsing support
XML annotations

Apache Juneau Overview

Table of Contents
  1. Juneau - What is it?

  2. Juneau Core (org.apache.juneau)

    1. Serializers

    2. Parsers

    3. SerializerGroups and ParserGroups

    4. ObjectMap and ObjectList

    5. Configurable Properties

    6. Transforms

      1. PojoSwaps

      2. Swap methods

      3. BeanFilters and @Bean annotations

    7. Bean Name and Dictionaries

      1. Bean Subtypes

    8. Virtual Beans

    9. POJO Categories

    10. Simple Variable Language

    11. Configuration Files

    12. Supported Languages

    13. Comparison with Jackson

  3. Juneau Data Transfer Objects (org.apache.juneau.dto)

    1. HTML5

    2. Atom

    3. Swagger

    4. JSON-Schema

  4. Juneau Server (

  5. Juneau Client (

  6. Remoteable services (

    1. Interface proxies against 3rd-party REST interfaces

  7. Juneau Microservices (org.apache.juneau.microservice)

  8. Samples

    1. Installing in Eclipse

    2. Running in Eclipse

    3. Building and Running from Command-Line


    5. RootResources

    6. HelloWorldResource

    7. MethodExampleResource

    8. UrlEncodedFormResource

    9. RequestEchoResource

    10. AddressBookResource

      1. Classes

      2. Demo

      3. Traversable

      4. Queryable

      5. Introspectable

      6. ClientTest

      7. Browser Tips

    11. SampleRemoteableServlet

    12. TempDirResource

    13. AtomFeedResource

    14. DockerRegistryResource

    15. TumblrParserResource

    16. PhotosResource

    17. JsonSchemaResource

    18. SqlQueryResource

    19. ConfigResource

    20. LogsResource

  9. Cookbook Examples

    1. Core API

    2. Server API

      1. Apply a transform that changes the format of doubles

      2. Apply transforms to a subset of serializers or parsers

    3. Client API

    4. Microservice API

  10. Best Practices

  11. Important Documentation Links

  12. Release Notes

1 - Juneau - What is it?

Juneau started off as a popular internal IBM toolkit called Juno. Originally used for serializing POJOs to and from JSON, it later expanded in scope to include a variety of content types, and then later REST servlet, client, and microservice APIs. It's use grew to more than 50 projects and was one of the most popular community source projects within IBM.

In 2016, the code was donated to the Apache Foundation under the project Apache Juneau.

  1. Extensive and extensible support for a large variety of POJOs, including structured data (beans) and unstructured data (Maps and Collections).

  2. Serialization support:

    • JSON (including variants)
    • XML
    • HTML
    • URL-Encoding
    • UON (URL-Encoded Object Notation)
    • MessagePack
    • RDF/XML
    • RDF/XML-Abbrev
    • N-Triple
    • Turtle
    • N3
    • SOAP/XML
  3. Parsing support:

    • JSON (including lax syntax, comments, concatenated strings)
    • XML
    • HTML
    • URL-Encoding
    • UON (URL-Encoded Object Notation)
    • MessagePack
    • RDF/XML
    • RDF/XML-Abbrev
    • N-Triple
    • Turtle
    • N3
  4. Data Transfer Objects:

    • HTML5
    • ATOM
    • Swagger
    • Cognos
    • JSON-Schema

    DTOs can be used with any serializers and parsers (e.g. ATOM as JSON).

  5. Serialization of POJO meta-models (e.g. the POJO class structure itself) to:

    • JSON-Schema
    • XML-Schema
    • HTML-Schema
  6. Serializers/parsers require only Java 6+. (RDF support requires Jena 2.7.1+)

  7. REST APIs require only Java 6+ and JEE 1.3+. (JAX/RS integration component requires JAX/RS provider)


Juneau ships as a single Java library called juneau.jar.

Juneau requires Java 6+. The majority of the code has no other dependencies except for the following packages:

OSGi bundles are also provided that break down Juneau into the following components:

  • org.apache.juneau.core.jar - Serializers, parsers, INI file support.
  • - REST servlet support.
  • - REST client support.
  • org.apache.juneau.microservice.jar - Microservice support.

The following zip files are also provided:

  • - Contains a template Eclipse project for quickly creating REST resources as executable jars.
  • - Contains sample code demonstrating various aspects of Juneau.
    These are discussed in detail in the Samples section.
  • Many of the examples below use beans with public field properties instead of standard getters/setters. This is to simplify the examples.

2 - Juneau Core (org.apache.juneau)

The core packages of Juneau contains serializers and parsers for converting POJOs to and from a wide variety of content types. It uses a common API for defining serializers and parsers.

One of the goals of Juneau was to make serialization as simple as possible. In a single line of code, you should be able to serialize and parse most POJOs. Despite this simplicity, Juneau provides lots of extensibility and configuration properties for tailoring how POJOs are serialized and parsed.

2.1 - Serializers

The built-in serializers in Juneau are fast, efficient, and highly configurable. They work by serializing POJOs directly to streams instead of using intermediate Document Object Model objects.

In most cases, you can serialize objects in one line of code by using one of the default serializers:

// A simple bean public class Person { public String name = "John Smith"; public int age = 21; } // Serialize to JSON, XML, or HTML Person p = new Person(); // Produces: // "{name:'John Smith',age:21}" String json = JsonSerializer.DEFAULT.serialize(p); // Produces: // <object> // <name>John Smith</name> // <age>21</age> // </object> String xml = XmlSerializer.DEFAULT.serialize(p); // Produces: // <table> // <tr><th>key</th><th>value</th></tr> // <tr><td>name</td><td>John Smith</td></tr> // <tr><td>age</td><td>21</td></tr> // </table> String html = HtmlSerializer.DEFAULT.serialize(p); // Produces: // "(name='John Smith',age=21)" String uon = UonSerializer.DEFAULT.serialize(p); // Produces: // "name='John+Smith'&age=21" String urlencoding = UrlEncodingSerializer.DEFAULT.serialize(p); // Produces: // 82 A4 6E 61 6D 65 AA 4A 6F 68 6E 20 53 6D 69 74 68 A3 61 67 65 15 byte[] b = MsgPackSerializer.DEFAULT.serialize(p);

In addition to the default serializers, customized serializers can be created using various built-in options:

// Use one of the default serializers to serialize a POJO String json = JsonSerializer.DEFAULT.serialize(someObject); // Create a custom serializer for lax syntax using single quote characters JsonSerializer serializer = new JsonSerializerBuilder().simple().sq().build(); // Clone an existing serializer and modify it to use single-quotes JsonSerializer serializer = JsonSerializer.DEFAULT.builder().sq().build(); // Serialize a POJO to JSON String json = serializer.serialize(someObject);

Default serialization support is provided for Java primitives, Maps, Collections, beans, and arrays.
Extensible support for other data types such as Calendars, Dates, Iterators is available through the use of POJO swaps (described later).

Additional Information

2.2 - Parsers

Parsers work by parsing input directly into POJOs instead of having to create intermediate Document Object Models. This allows them to parse input with minimal object creation.

Like the serializers, you can often parse objects in one line of code by using one of the default parsers:

// Use one of the predefined parsers. Parser parser = JsonParser.DEFAULT; // Parse a JSON object as a bean. String json = "{name:'John Smith',age:21}"; Person p = parser.parse(json, Person.class); // Or parse it into a generic Map. Map m1 = parser.parse(json, Map.class); // Parse a JSON string. json = "'foobar'"; String s2 = parser.parse(json, String.class); // Parse a JSON number as a Long or Float. json = "123"; Long l3 = parser.parse(json, Long.class); Float f3 = parser.parse(json, Float.class); // Parse a JSON object as a HashMap<String,Person>. json = "{a:{name:'John Smith',age:21},b:{name:'Joe Smith',age:42}}"; Map<String,Person> m4 = parser.parse(json, HashMap.class, String.class, Person.class) // Parse a JSON object as a HashMap<String,LinkedList<Person>>. json = "{a:[{name:'John Smith',age:21},{name:'Joe Smith',age:42}]}"; Map<String,List<Person>> m5 = parser.parse(json, HashMap.class, String.class, LinkedList.class, Person.class) // Parse a JSON array of integers as a Collection of Integers or int[] array. json = "[1,2,3]"; List<Integer> l6 = parser.parse(json, LinkedList.class, Integer.class); int[] i7 = parser.parse(json, int[].class);

The parsers can also be used to populating existing bean and collection objects:

// Use one of the predefined parsers. Parser parser = JsonParser.DEFAULT; // Populate the properties on an existing bean from a JSON object. String json = "{name:'John Smith',age:21}"; Person p = new Person(); parser.parseIntoBean(json, p); // Populate an existing list from a JSON array of numbers. json = "[1,2,3]"; List<Integer> l2 = new LinkedList<Integer>(); parser.parseIntoCollection(json, l2, Integer.class); // Populate an existing map from a JSON object containing beans. json = "{a:{name:'John Smith',age:21},b:{name:'Joe Smith',age:42}}"; Map<String,Person> m3 = new TreeMap<String,Person>(); parser.parseIntoMap(json, m3, String.class, Person.class);

  • In the example above, we're parsing "lax" JSON (single quotes, unquoted attributes). The JSON parser can handle any valid JSON syntax (such as quoted or unquoted attributes, single or double quotes).
    It can also handle JSON fragements and embedded Javascript comments. Many of the JSON examples provided will use lax syntax which is easier to read since we don't have to deal with escapes.
Additional Information

2.3 - SerializerGroups and ParserGroups

Above the serializers and parsers are the SerializerGroup and ParserGroup classes. These classes allow serializers and parsers to be retrieved by W3C-compliant HTTP Accept and Content-Type values...

// Construct a new serializer group with configuration parameters that get applied to all serializers. SerializerGroup sg = new SerializerGroupBuilder() .append(JsonSerializer.class, UrlEncodingSerializer.class); .ws // or .useWhitespace(true) .pojoSwaps(CalendarSwap.ISO8601DT.class) .build(); // Find the appropriate serializer by Accept type and serialize our POJO to the specified writer. sg.getSerializer("text/invalid, text/json;q=0.8, text/*;q:0.6, *\/*;q=0.0") .serialize(myPersonObject, myWriter); // Construct a new parser group with configuration parameters that get applied to all parsers. ParserGroup pg = new ParserGroupBuilder() .append(JsonSerializer.class, UrlEncodingSerializer.class); .pojoSwaps(CalendarSwap.ISO8601DT.class) .build(); Person p = pg.getParser("text/json").parse(myReader, Person.class);

The REST servlet API builds upon the SerializerGroup and ParserGroup classes to provide annotated REST servlets that automatically negotiate the HTTP media types and allow the developer to work with requests and responses as POJOs.

Additional Information

2.4 - ObjectMap and ObjectList

The ObjectMap and ObjectList classes are generic Java representations of JSON objects and arrays. These classes can be used to create "unstructured" models for serialization (as opposed to "structured" models consisting of beans). If you want to quickly generate JSON/XML/HTML from generic maps/collections, or parse JSON/XML/HTML into generic maps/collections, these classes work well.

These classes extend directly from the following JCF classes:

The ObjectMap and ObjectList classes are very similar to the JSONObject and JSONArray classes found in other libraries. However, the names were chosen because the concepts of Maps and Lists are already familiar to Java programmers, and these classes can be used with any of the serializers or parsers.

These object can be serialized in one of two ways:

  1. Using the provided ObjectMap.serializeTo( or ObjectList.serializeTo( methods.
  2. Passing them to one of the Serializer serialize methods.

Any valid JSON can be parsed into an unstructured model consisting of generic ObjectMap and ObjectList objects.

// Parse an arbitrary JSON document into an unstructered data model // consisting of ObjectMaps, ObjectLists, and java primitive objects. Parser parser = JsonParser.DEFAULT; String json = "{a:{name:'John Smith',age:21},b:{name:'Joe Smith',age:42}}"; ObjectMap m = parser.parse(json, ObjectMap.class); // Use ObjectMap API to extract data from the unstructured model. int johnSmithAge = m.getObjectMap("a").getInt("age"); // Convert it back into JSON. json = JsonSerializer.DEFAULT.serialize(m); // Or convert it to XML. String xml = XmlSerializer.DEFAULT.serialize(m);

  • As a general rule, if you do not specify a target type during parsing, or if the target type cannot be determined through reflection, the parsers automatically generate ObjectMaps and ObjectLists.
Additional Information

2.5 - Configurable Properties

Serializers and parsers have a wide variety of configurable properties.
For example, the following code shows how to configure a JSON serializer:

JsonSerializer s = new JsonSerializerBuilder().simple().ws().sq().build();

However, each of the serializers and parsers already contain reusable instances with common configurations.
For example, JSON has the following predefined reusable serializers and parsers:

These can be used directly, as follows:

// Serialize a POJO to LAX JSON. String json = JsonSerializer.DEFAULT_LAX.serialize(myPojo);

Serializers and parsers can be locked to prevent further modification to the properties. They can also be cloned to copy the configuration of other serializers and parsers.

// Clone and customize an existing serializer. JsonSerializer s = JsonSerializer.DEFAULT_LAX .builder() .quoteChar('"') .build(); // Lock it so that the configuration cannot be changed. s.lock();

Additional Information

The following is a list of all configurable properties across all serializers and parsers.

2.6 - Transforms

By default, the Juneau framework can serialize and parse a wide variety of POJOs out-of-the-box. However, two special classes are provided tailor how certain Java objects are handled by the framework. These classes are:

  • PojoSwap - Tailor how specific non-bean classes are handled by the framework.
  • BeanFilter - Tailor how specific bean classes are handled by the framework.

Annotations are also provided that allow you to use transformations directly on class definitions:

  • @Pojo - Used to tailor how non-bean POJOs get interpreted by the framework.
  • @Bean - Used to tailor how beans get interpreted by the framework.
  • @BeanConstructor - Maps constructor arguments to property names on beans with read-only properties.
  • @BeanIgnore - Ignore classes, fields, and methods from being interpreted as bean or bean components.
  • @BeanProperty - Used to tailor how bean properties get interpreted by the framework.
  • @NameProperty - Identifies a setter as a method for setting the name of a POJO as it's known by its parent object.
  • @ParentProperty - Identifies a setter as a method for adding a parent reference to a child object.
  • @URI - Used to identify a class or bean property as a URI.

2.6.1 - PojoSwaps

PojoSwaps are a critical component of Juneau. They allow the serializers and parsers to handle Java objects that wouldn't normally be serializable.

Swaps are very easy to understand. Simply put, they can be thought of as 'object swappers' that swap in serializable objects for non-serializable ones during serialization, and vis-versa during parsing.

Some examples of non-serializable POJOs are File, Reader, Iterable, etc... These are classes that aren't beans and cannot be represented as simple maps, collections, or primitives.

In the following example, we introduce a PojoSwap that will swap in ISO8601 strings for Date objects:

// Sample swap for converting Dates to ISO8601 strings. public class MyDateSwap extends PojoSwap<Date,String> { // ISO8601 formatter. private DateFormat format = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ssZ"); /** Converts a Date object to an ISO8601 string. */ @Override public String swap(BeanSession session, Date o) { return format.format(o); } /** Converts an ISO8601 string to a Date object. */ @Override public Date unswap(BeanSession session, String o, ClassMeta hint) throws ParseException { try { return format.parse(o); } catch (java.text.ParseException e) { throw new ParseException(e); } } }

The swap can then be associated with serializers and parsers like so:

// Sample bean with a Date field. public class MyBean { public Date date = new Date(112, 2, 3, 4, 5, 6); } // Create a new JSON serializer, associate our date swap with it, and serialize a sample bean. Serializer serializer = new JsonSerializerBuilder().pojoSwaps(MyDateSwap.class).build(); String json = serializer.serialize(new MyBean()); // == "{date:'2012-03-03T04:05:06-0500'}" // Create a JSON parser, associate our date swap with it, and reconstruct our bean (including the date). ReaderParser parser = new JsonParserBuilder().pojoSwaps(MyDateSwap.class).build(); MyBean bean = parser.parse(json, MyBean.class); int day =; // == 3

Several PojoSwaps are already provided for common Java objects:

In particular, the CalendarSwap and DateSwap tramsforms provide a large number of customized swaps to ISO, RFC, or localized strings.

  • The 'swapped' class type must be a serializable type.
    See the definition for Category 4 objects in POJO Categories.

2.6.2 - Swap methods

Various methods can be defined on a class directly to affect how it gets serialized. This can often be simpler than using PojoSwaps.

Objects serialized as Strings can be parsed back into their original objects by implementing one of the following methods on the class:

  • public static T fromString(String) method.
    Any of the following method names also work:
    • valueOf(String)
    • parse(String)
    • parseString(String)
    • forName(String)
    • forString(String)
  • public T(String) constructor.

Note that these methods cover conversion from several built-in Java types, meaning the parsers can automatically construct these objects from strings:

If you want to force a bean-like class to be serialized as a string, you can use the @BeanIgnore annotation on the class to force it to be serialized to a string using the toString() method.

Serializing to other intermediate objects can be accomplished by defining a swap method directly on the class:

  • public X swap(BeanSession) method, where X is any serializable object.

The BeanSession parameter allows you access to various information about the current serialization session. For example, you could provide customized results based on the media type being produced (BeanSession.getMediaType()).

The following example shows how an HTML5 form template object can be created that gets serialized as a populated HTML5 Form bean.

import static org.apache.juneau.dto.html5.HtmlBuilder.*; /** * A simple HTML form template whose serialized form is an HTML5 Form object. */ public class FormTemplate { private String action; private int value1; private boolean value2; // Some constructor that initializes our fields. public FormTemplate(String action, int value1, boolean value2) { this.action = action; this.value1 = value1; this.value2 = value2; } // Special swap method that converts this template to a serializable bean public Form swap(BeanSession session) { return form(action, input("text").name("v1").value(value1), input("text").name("v2").value(value2) ); } }

Swapped objects can be converted back into their original form by the parsers by specifying one of the following methods:

  • public static T unswap(BeanSession, X) method where X is the swap class type.
  • public T(X) constructor where X is the swap class type.

The following shows how our form template class can be modified to allow the parsers to reconstruct our original object:

import static org.apache.juneau.dto.html5.HtmlBuilder.*; /** * A simple HTML form template whose serialized form is an HTML5 Form object. * This time with parsing support. */ @Bean(beanDictionary=HtmlBeanDictionary.class) public class FormTemplate { private String action; private int value1; private boolean value2; // Our 'unswap' constructor public FormTemplate(Form f) { this.action = f.getAttr("action"); this.value1 = f.getChild(Input.class, 0).getAttr(int.class, "value"); this.value2 = f.getChild(Input.class, 1).getAttr(boolean.class, "value"); } public FormTemplate(String action, int value1, boolean value2) { this.action = action; this.value1 = value1; this.value2 = value2; } public Form swap(BeanSession session) { return form(action, input("text").name("v1").value(value1), input("text").name("v2").value(value2) ); } }

2.6.3 - BeanFilters and @Bean annotations

BeanFilters are used to control aspects of how beans are handled during serialization and parsing. They allow you to control various aspects of beans, such as...

  • Which properties to include or exclude.
  • Property order.
  • Property naming conventions.
  • Overriding reading and writing of properties.

In practice, however, it's simpler to use the @Bean and @BeanProperty annotations on your bean classes. The annotations are functionally equivalent to the bean filter class.

// Address class with only street/city/state properties (in that order). // All other properties are ignored. @Bean(properties="street,city,state") public class Address { ...

Bean filters are defined through BeanFilterBuilders. The programmatic equivalent to the the annotation above would be:

public class MyAddressBeanFilter extends BeanFilterBuilder { // Must provide a no-arg constructor! public MyAddressBeanFilter() { super(Address.class); // The bean class that this filter applies to. setIncludeProperties("street,city,state"); // The properties we want exposed. } }

Bean filters are added to serializers and parsers using the *BeanFilters(Class...) methods. For example:

// Create a new JSON serializer and associate a bean filter with it. Serializer serializer = new JsonSerializerBuilder().beanFilters(MyAddressBeanFilter.class).build();

Note that if you use the annotation, you do NOT need to set anything on the serializers/parsers. The annotations will be detected and bean filters will automatically be created for them.

The addBeanFilter(Class...) method also allows you to pass in interfaces. Any class that's not a subclass of BeanFilterBuilder get interpreted as bean interface classes. These cause bean implementations of those interfaces to only expose the properties defined on the interface.

// An interface with the 3 properties we want serialized. public interface AddressInterface { public String getStreet(); public String getCity(); public String getState(); } // Our bean implementation. public class Address implements AddressInterface { ... } // Create a new JSON serializer that only exposes street,city,state on Address bean. Serializer serializer = new JsonSerializerBuilder().beanFilters(AddressInterface.class).build();

Additional Information

2.7 - Bean Names and Dictionaries

While parsing into beans, Juneau attempts to determine the class types of bean properties through reflection on the bean property getter or setter. Often this is insufficient if the property type is an interface or abstract class that cannot be instantiated. This is where bean names and dictionaries come into play.

Bean names and dictionary are used for identifying class types when they cannot be inferred through reflection.

Bean classes are given names through the @Bean.typeName() annotation. These names are then added to the serialized output as virtual "_type" properties (or element names in XML).

On the parsing side, these type names are resolved to classes through the use of bean dictionaries.

For example, if a bean property is of type Object, then the serializer will add "_type" attributes so that the class can be determined during parsing.

@Bean(typeName="foo") public class Foo { // A bean property where the object types cannot be inferred since it's an Object[]. @BeanProperty(typeDictionary={Bar.class,Baz.class}) public Object[] x = new Object[]{new Bar(), new Baz()}; } @Bean(typeName="bar") public class Bar {} @Bean(typeName="baz") public class Baz {}

When serialized as JSON, "_type" attributes would be added when needed to infer the type during parsing:

{ x: [ {_type:'bar'}, {_type:'baz'} ] }

Type names can be represented slightly differently in different languages. For example, the dictionary name is used as element names when serialized to XML. This allows the typeName annotation to be used as a shortcut for defining element names for beans.

When serialized as XML, the bean is rendered as:

<foo> <x> <bar/> <baz/> </x> </foo>

Bean dictionaries are defined at two levels:

  • Type names do not need to be universally unique. However, they must be unique within a dictionary.
  • The following reserved words cannot be used as type names: object, array, number, boolean, null.
  • Serialized type names are DISABLED by default. They must be enabled on the serializer using the SerializerContext.SERIALIZER_addBeanTypeProperties configuration property.
  • The "_type" property name can be overridden using the BeanContext.BEAN_beanTypePropertyName configuration property.

2.7.1 - Bean Subtypes

In addition to the bean type name support described above, simplified support is provided for bean subtypes.

Bean subtypes are similar in concept to bean type names, except for the following differences:

  • You specify the list of possible subclasses through an annotation on a parent bean class.
  • You do not need to register the subtype classes on the bean dictionary of the parser.

In the following example, the abstract class has two subclasses:

// Abstract superclass @Bean( beanDictionary={A1.class, A2.class} ) public abstract class A { public String f0 = "f0"; } // Subclass 1 @Bean(typeName="A1") public class A1 extends A { public String f1; } // Subclass 2 @Bean(typeName="A2") public class A2 extends A { public String f2; }

When serialized, the subtype is serialized as a virtual "_type" property:

JsonSerializer s = JsonSerializer.DEFAULT_LAX; A1 a1 = new A1(); a1.f1 = "f1"; String r = s.serialize(a1); assertEquals("{_type:'A1',f1:'f1',f0:'f0'}", r);

The following shows what happens when parsing back into the original object.

JsonParser p = JsonParser.DEFAULT; A a = p.parse(r, A.class); assertTrue(a instanceof A1);

2.8 - Virtual Beans

The BeanContext.BEAN_useInterfaceProxies setting (enabled by default) allows the Juneau parsers to parse content into virtual beans (bean interfaces without implementation classes).

For example, the following code creates an instance of the specified unimplemented interface:

// Our unimplemented interface public interface Address { String getStreet(); void setStreet(String x); String getCity(); void setCity(String x); StateEnum getState(); void setState(StateEnum x); int getZip(); void setZip(int zip); } // Our code Address address = JsonParser.DEFAULT.parse( "{street:'123 Main St', city:'Anywhere', state:'PR', zip:12345}", Address.class ); int zip = address.getZip(); address.setState(StateEnum.NY);

Getter and setter values can be any parsable values, even other virtual beans.

Under-the-covers, a virtual bean is simply a proxy interface on top of an existing BeanMap instance. From a programmatic point-of-view, they're indistinguishable from real beans, and can be manipulated and serialized like any other bean.

Virtual beans can also be created programmatically using the BeanContext class:

Address address = BeanContext.DEFAULT.createSession().newBean(Address.class);

2.9 - POJO Categories

The following chart shows POJOs categorized into groups and whether they can be serialized or parsed:

1 Java primitive objects
  • String
  • Integer
  • Float
  • Boolean
yes yes
2 Java Collections Framework objects and Java arrays      
2a With standard keys/values
Map keys are group [1, 4a, 5a] objects.
Map, Collection, and array values are group [1, 2, 3ac, 4a, 5a] objects.
  • HashSet<String,Integer>
  • TreeMap<Integer,Bean>
  • List<int[][]>
  • Bean[]
yes yes
2b With non-standard keys/values
Map keys are group [2, 3, 4b, 5b, 6] objects.
Map, Collection, and array values are group [3b, 4b, 5b, 6] objects.
  • HashSet<Bean,Integer>
  • TreeMap<Integer,Reader>
yes no
3 Java Beans      
3a With standard properties
These are beans that have no-arg constructors and one or more properties defined by public getter and setter methods or public fields.
Property values are group [1, 2, 3ac, 4a, 5a] objects.
  yes yes
3b With non-standard properties or not true beans
These include true beans that have no-arg constructors and one or more properties defined by getter and setter methods or properties, but property types include group [3b, 4b, 5b, 6] objects.
This also includes classes that look like beans but aren't true beans. For example, classes that have getters but not setters, or classes without no-arg constructors.
  yes no
3c Virtual beans
These are unimplemented bean interfaces with properties of type [1, 2, 3ac, 4a, 5a] objects.
Parsers will automatically create interface proxies on top of BeanMap instances.
  yes yes
4 Swapped objects
These are objects that are not directly serializable, but have PojoSwaps associated with them. The purpose of a POJO swap is to convert an object to another object that is easier to serialize and parse. For example, the DateSwap.ISO8601DT class can be used to serialize Date objects to ISO8601 strings, and parse them back into Date objects.
4a 2-way swapped to group [1, 2a, 3ac] objects
For example, a swap that converts a Date to a String.
  • java.util.Date
  • java.util.GregorianCalendar
yes yes
4b 1-way swapped to group [1, 2, 3] objects
For example, a swap that converts an Iterator to a List. This would be one way, since you cannot reconstruct an Iterator.
  • java.util.Iterator
yes no
5 Non-serializable objects with standard methods for converting to a serializable form
5a Classes with a method that converts it to a serializable form:
  • public X swap(BeanSession); where X is in groups [1, 2a, 3ac].
  • public String toString(); where the string is any meaningful data.
And a method that converts it back into the original object:
  • public static T fromString(String);
  • public static T valueOf(String);
  • public static T parse(String);
  • public static T parseString(String);
  • public static T forName(String);
  • public static T forString(String);
  • public T(X); where X is in groups [1, 2a, 3ac].
  • public static T unswap(BeanSession,X); where X is in groups [1, 2a, 3ac].
  • java.lang.Class
  • java.sql.Time
  • java.sql.Timestamp
  • java.text.MessageFormat
  • java.text.NumberFormat
  • java.util.Date
  • java.util.UUID
  • java.util.logging.Level
  • javax.xml.bind.DatatypeConverter
yes yes
5b Classes that only have a method to convert to a serializable form:
  • public X swap(BeanSession); where X is in groups [1, 2, 3].
  • public String toString(); where the string is any meaningful data.
  yes no
6 All other objects
Anything that doesn't fall into one of the groups above are simply converted to Strings using the toString() method.
  yes no
  • Serializers are designed to work on tree-shaped POJO models. These are models where there are no referential loops (e.g. leaves with references to nodes, or nodes in one branch referencing nodes in another branch). There is a serializer setting detectRecursions to look for and handle these kinds of loops (by setting these references to null), but it is not enabled by default since it introduces a moderate performance penalty.

2.10 - Simple Variable Language

The org.apache.juneau.svl package defines an API for a language called "Simple Variable Language". In a nutshell, Simple Variable Language (or SVL) is text that contains variables of the form "$varName{varKey}".

Variables can be recursively nested within the varKey (e.g. "$FOO{$BAR{xxx},$BAZ{xxx}}"). Variables can also return values that themselves contain more variables.

// Use the default variable resolver to resolve a string that contains $S (system property) variables String myProperty = VarResolver.DEFAULT.resolve("The Java home directory is $S{java.home}");

The following shows how variables can be arbitrarily nested...

// Look up a property in the following order: // 1) MYPROPERTY environment variable. // 2) '' system property if environment variable not found. // 3) 'not found' string if system property not found. String myproperty = VarResolver.DEFAULT.resolve("$E{MYPROPERTY,$S{,not found}}");

SVL is a large topic on it's own. It is used extensively in the ConfigFile, REST and Microservice APIs.

Additional Information

2.11 - Configuration Files

The org.apache.juneau.ini package contains a powerful API for creating and using INI-style config files.

An example of an INI file:

# Default section key1 = 1 key2 = true key3 = [1,2,3] key4 = http://foo # Section 1 [Section1] key1 = 2 key2 = false key3 = [4,5,6] key4 = http://bar

This class can be used to easily access contents of the file:

int key1; boolean key2; int[] key3; URL key4; // Load our config file ConfigFile f = new ConfigFileBuilder().build("MyConfig.cfg"); // Read values from default section key1 = f.getInt("key1"); key2 = f.getBoolean("key2"); key3 = f.getObject(int[].class, "key3"); key4 = f.getObject(URL.class, "key4"); // Read values from section #1 key1 = f.getInt("Section1/key1"); key2 = f.getBoolean("Section1/key2"); key3 = f.getObject(int[].class, "Section1/key3"); key4 = f.getObject(URL.class, "Section1/key4");

The interface also allows a config file to be easily constructed programmatically:

// Construct the sample INI file programmatically ConfigFile cf = new ConfigFileBuilder().build("MyConfig.cfg") .addLines(null, "# Default section", "key1 = 1", "key2 = true", "key3 = [1,2,3]", "key4 = http://foo", "") .addHeaderComments("Section1", "# Section 1") .addLines("Section1", "key1 = 2", "key2 = false", "key3 = [4,5,6]", "key4 = http://bar") .save();

The following is equivalent, except that it uses ConfigFile.put(String, Object) to set values:

// Construct the sample INI file programmatically ConfigFile cf = new ConfigFileBuilder().build("MyConfig.cfg") .addLines(null, "# Default section") .addHeaderComments("section1", "# Section 1"); cf.put("key1", 1); cf.put("key2", true); cf.put("key3", new int[]{1,2,3}); cf.put("key4", new URL("http://foo")); cf.put("Section1/key1", 2); cf.put("Section1/key2", false); cf.put("Section1/key3", new int[]{4,5,6}); cf.put("Section1/key4", new URL("http://bar"));;

Values are LAX JSON (i.e. unquoted attributes, single quotes) except for top-level strings which are left unquoted. Any parsable object types are supported as values (e.g. arrays, collections, beans, swappable objects, enums, etc...).

The config file looks deceptively simple, the config file API is a very powerful feature with many capabilities, including:

  • The ability to use variables to reference environment variables, system properties, other config file entries, and a host of other types.
  • APIs for updating, modifying, and saving configuration files without losing comments or formatting.
  • Extensive listener APIs.

#-------------------------- # My section #-------------------------- [MySection] # An integer anInt = 1 # A boolean aBoolean = true # An int array anIntArray = [1,2,3] # A POJO that can be converted from a String aURL = http://foo # A POJO that can be converted from JSON aBean = {foo:'bar',baz:123} # A system property locale = $S{java.locale, en_US} # An environment variable path = $E{PATH, unknown} # A manifest file entry mainClass = $MF{Main-Class} # Another value in this config file sameAsAnInt = $C{MySection/anInt} # A command-line argument in the form "myarg=foo" myArg = $ARG{myarg} # The first command-line argument firstArg = $ARG{0} # Look for system property, or env var if that doesn't exist, or command-line arg if that doesn't exist. nested = $S{mySystemProperty,$E{MY_ENV_VAR,$ARG{0}}} # A POJO with embedded variables aBean2 = {foo:'$ARG{0}',baz:$C{MySection/anInt}}

// Java code for accessing config entries above. ConfigFile cf = Microservice.getConfig(); int anInt = cf.getInt("MySection/anInt"); boolean aBoolean = cf.getBoolean("MySection/aBoolean"); int[] anIntArray = cf.getObject(int[].class, "MySection/anIntArray"); URL aURL = cf.getObject(URL.class, "MySection/aURL"); MyBean aBean = cf.getObject(MyBean.class, "MySection/aBean"); Locale locale = cf.getObject(Locale.class, "MySection/locale"); String path = cf.getString("MySection/path"); String mainClass = cf.getString("MySection/mainClass"); int sameAsAnInt = cf.getInt("MySection/sameAsAnInt"); String myArg = cf.getString("MySection/myArg"); String firstArg = cf.getString("MySection/firstArg");

Config files can also be used to directly populate beans using the ConfigFile.getSectionAsBean(String,Class,boolean):

// Example config file [MyAddress] name = John Smith street = 123 Main Street city = Anywhere state = NY zip = 12345 // Example bean public class Address { public String name, street, city; public StateEnum state; public int zip; } // Example usage ConfigFile cf = new ConfigFileBuilder().build("MyConfig.cfg"); Address myAddress = cf.getSectionAsBean("MySection", Address.class);

Config file sections can also be accessed via interface proxies using ConfigFile.getSectionAsInterface(String,Class):

// Example config file [MySection] string = foo int = 123 enum = ONE bean = {foo:'bar',baz:123} int3dArray = [[[123,null],null],null] bean1d3dListMap = {key:[[[[{foo:'bar',baz:123}]]]]} // Example interface public interface MyConfigInterface { String getString(); void setString(String x); int getInt(); void setInt(int x); MyEnum getEnum(); void setEnum(MyEnum x); MyBean getBean(); void setBean(MyBean x); int[][][] getInt3dArray(); void setInt3dArray(int[][][] x); Map<String,List<MyBean[][][]>> getBean1d3dListMap(); void setBean1d3dListMap(Map<String,List<MyBean[][][]>> x); } // Example usage ConfigFile cf = new ConfigFileBuilder().build("MyConfig.cfg"); MyConfigInterface ci = cf.getSectionAsInterface("MySection", MyConfigInterface.class); int myInt = ci.getInt(); ci.setBean(new MyBean());;

Additional Information

2.12 - Supported Languages

Extensive javadocs exist for individual language support. Refer to these docs for language-specific information.

Additional Information

2.13 - Comparison with Jackson

Juneau was developed independently from Jackson, but shares many of the same features and capabilities. Whereas Jackson was created to work primariliy with JSON, Juneau was created to work for multiple languages. Therefore, the terminology and annotations in Juneau are similar, but language-agnostic.

The following charts describe equivalent features between the two libraries:

@JsonIgnoreProperties({...}) @Bean(excludeProperties="...")
@JsonAutoDetect(fieldVisibility=...) No equivalent annotation, but can be controlled via:
Future annotation support planned.
@JacksonInject No equivalent.
Future support planned.
Juneau uses swaps to convert non-serializable object to serializable forms:
@JsonInclude No equivalent annotation, but can be controlled via various settings:
Future annotation support planned.
@JsonPropertyOrder @Bean(properties="...")
No equivalents.
Future support unlikely since these are JSON-centric.

3 - Juneau Data Transfer Objects (org.apache.juneau.dto)

The Juneau Core library contains several predefined POJOs for generating commonly-used document types. This section describes support for these POJOs.

3.1 - HTML5

The Juneau HTML5 DTOs are simply beans with fluent-style setters that allow you to quickly construct HTML fragments as Java objects. These object can then be serialized to HTML using one of the existing HTML serializers, or to other languages such as JSON using the JSON serializers.

The HtmlBuilder class is a utility class with predefined static methods that allow you to easily construct DTO instances in a minimal amount of code.

The following examples show how to create HTML tables.

Java code HTML
import static org.apache.juneau.dto.html5.HtmlBuilder.*; Object mytable = table( tr( th("c1"), th("c2") ), tr( td("v1"), td("v2") ) ); String html = HtmlSerializer.DEFAULT.serialize(mytable); <table> <tr> <th>c1</th> <th>c2</th> </tr> <tr> <td>v1</td> <td>v2</td> </tr> </table>
import static org.apache.juneau.dto.html5.HtmlBuilder.*; Object mydiv = div().align("center").onmouseover("alert(\"boo!\");") .children( p("Juneau supports ", b(i("mixed")), " content!") ); String html = HtmlSerializer.DEFAULT.serialize(mydiv); <div align='center' onmouseover='alert("boo!");'> <p>Juneau supports <b><i>mixed</i></b> content!</p> </table>
import static org.apache.juneau.dto.html5.HtmlBuilder.*; Object myform = form().action("/submit").method("POST") .children( "Position (1-10000): ", input("number").name("pos").value(1), br(), "Limit (1-10000): ", input("number").name("limit").value(100), br(), button("submit", "Submit"), button("reset", "Reset") ); String html = HtmlSerializer.DEFAULT.serialize(myform); <form action='/submit' method='POST'> Position (1-10000): <input name='pos' type='number' value='1'/><br/> Limit (1-10000): <input name='pos' type='number' value='100'/><br/> <button type='submit'>Submit</button> <button type='reset'>Reset</button> </form>

Using the HTML5 DTOs, you should be able to construct any valid HTML5 from full document bodies to any possible fragements.

The HtmlParser class can be used convert these HTML documents back into POJOs.

Other serializers and parsers (e.g. JsonSerializer) can be used to represent these POJOs in languages other than HTML.

Additional Information

3.2 - Atom

The Juneau ATOM feed DTOs are simply beans with fluent-style setters.
The following code shows a feed being created programmatically using the AtomBuilder class.

import static org.apache.juneau.dto.atom.AtomBuilder.*; Feed feed = feed("", "Juneau ATOM specification", "2016-01-02T03:04:05Z") .subtitle(text("html").text("Describes <em>stuff</em> about Juneau")) .links( link("alternate", "text/html", "").hreflang("en"), link("self", "application/atom+xml", "") ) .rights("Copyright (c) 2016, Apache Foundation") .generator( generator("Juneau").uri("").version("1.0") ) .entries( entry(",2013:1.2345", "Juneau ATOM specification snapshot", "2016-01-02T03:04:05Z") .links( link"alternate", "text/html", ""), link("enclosure", "audio/mpeg", "").length(1337) ) .published("2016-01-02T03:04:05Z") .authors( person("Jane Smith").uri("").email("") ) .contributors( person("John Smith") ) .content( content("xhtml") .lang("en") .base("") .text("<div><p><i>[Update: Juneau supports ATOM.]</i></p></div>") ) );

To serialize this to ATOM, use the XmlSerializer class:

Example with no namespaces

// Create a serializer with readable output, no namespaces yet. XmlSerializer s = new XmlSerializerBuilder().sq().ws().build(); // Serialize to ATOM/XML String atomXml = s.serialize(feed);


<feed> <id> </id> <link href='' rel='alternate' type='text/html' hreflang='en'/> <link href='' rel='self' type='application/atom+xml'/> <rights> Copyright (c) 2016, Apache Foundation </rights> <title type='text'> Juneau ATOM specification </title> <updated>2016-01-02T03:04:05Z</updated> <generator uri='' version='1.0'> Juneau </generator> <subtitle type='html'> Describes <em>stuff</em> about Juneau </subtitle> <entry> <author> <name>Jane Smith</name> <uri></uri> <email></email> </author> <contributor> <name>John Smith</name> </contributor> <id> </id> <link href='' rel='alternate' type='text/html'/> <link href='' rel='enclosure' type='audio/mpeg' length='12345'/> <title> Juneau ATOM specification snapshot </title> <updated>2016-01-02T03:04:05Z</updated> <content base='' lang='en' type='xhtml'> <div xmlns=""><p><i>[Update: Juneau supports ATOM.]</i></p></div> </content> <published>2016-01-02T03:04:05Z</published> </entry> </feed>

The XmlParser class can be used convert these Atom documents back into POJOs.

Other serializers and parsers (e.g. JsonSerializer) can be used to represent these POJOs in languages other than XML.

Additional Information

3.3 - Swagger

The Juneau Swagger DTOs are simply beans with fluent-style setters that allow you to quickly construct Swagger documents as Java objects. These object can then be serialized to JSON using one of the existing JSON serializers, or to other languages such as XML or HTML using the other serializers.

The SwaggerBuilder class is a utility class with predefined static methods that allow you to easily construct DTO instances in a minimal amount of code.

The following is an example Swagger document from the Swagger website.

{ "swagger": "2.0", "info": { "title": "Swagger Petstore", "description": "This is a sample server Petstore server.", "version": "1.0.0", "termsOfService": "", "contact": { "email": "" }, "license": { "name": "Apache 2.0", "url": "" } }, "host": "", "basePath": "/v2", "tags": [ { "name": "pet", "description": "Everything about your Pets", "externalDocs": { "description": "Find out more", "url": "" } } ], "schemes": [ "http" ], "paths": { "/pet": { "post": { "tags": [ "pet" ], "summary": "Add a new pet to the store", "description": "", "operationId": "addPet", "consumes": [ "application/json", "text/xml" ], "produces": [ "application/json", "text/xml" ], "parameters": [ { "in": "body", "name": "body", "description": "Pet object that needs to be added to the store", "required": true } ], "responses": { "405": { "description": "Invalid input" } } } } }, }

This document can be generated by the following Java code:

static import org.apache.juneau.dto.swagger.SwaggerBuilder.*; Swagger swagger = swagger() .swagger("2.0") .info( info("Swagger Petstore", "1.0.0") .description("This is a sample server Petstore server.") .termsOfService("") .contact( contact().email("") ) .license( license("Apache 2.0").url("") ) ) .host("") .basePath("/v2") .tags( tag("pet").description("Everything about your Pets") .externalDocs( externalDocumentation("", "") ) ) .schemes("http") .path("/pet", "post", operation() .tags("pet") .summary("Add a new pet to the store") .description("") .operationId("addPet") .consumes(MediaType.JSON, MediaType.XML) .produces(MediaType.JSON, MediaType.XML) .parameters( parameterInfo("body", "body") .description("Pet object that needs to be added to the store") .required(true) ) .response(405, responseInfo("Invalid input")) ); String swaggerJson = JsonSerializer.DEFAULT_READABLE.serialize(swagger);

Swagger docs can be parsed back into Swagger beans using the following code:

Swagger swagger = JsonParser.DEFAULT.parse(swaggerJson, Swagger.class);

3.4 - JSON-Schema


4 - Juneau Server (

The Juneau REST Server API provides servlet-based REST resources on top of existing POJOs.

The API automatically detects Accept header of requests and converts POJOs to any of the supported languages. The toolkit is extensible and also allows for support of user-defined content types.

Automatic built-in support is provided for negotiation of response charsets and gzip encoding.

The following is an example of a REST API used to view and set JVM system properties.

@RestResource( path="/systemProperties", // Title and description that show up on HTML rendition page. // Also used in Swagger doc. title="System properties resource", description="REST interface for performing CRUD operations on system properties.", // Links on the HTML rendition page. // "request:/..." URIs are relative to the request URI. // "servlet:/..." URIs are relative to the servlet URI. htmldoc=@HtmlDoc( links="{up:'request:/..',options:'servlet:/?method=OPTIONS'}" ), // Properties that get applied to all serializers and parsers. properties={ // Use single quotes. @Property(name=SERIALIZER_quoteChar, value="'") }, // Our stylesheet for the HTML rendition. stylesheet="styles/devops.css", // Support GZIP encoding on Accept-Encoding header. encoders=GzipEncoder.class, // Swagger info. swagger=@ResourceSwagger( contact="{name:'John Smith',email:''}", license="{name:'Apache 2.0',url:''}", version="2.0", termsOfService="You're on your own.", tags="[{name:'Java',description:'Java utility',externalDocs:{description:'Home page',url:''}}]", externalDocs="{description:'Home page',url:''}" ) ) public class SystemPropertiesResource extends RestServletDefault { @RestMethod( name="GET", path="/", summary="Show all system properties", description="Returns all system properties defined in the JVM.", parameters={ @Parameter(in="query", name="sort", description="Sort results alphabetically.", _default="false") }, responses={ @Response(value=200, description="Returns a map of key/value pairs.") } ) public Map getSystemProperties(@Query("sort") boolean sort) throws Throwable { if (sort) return new TreeMap(System.getProperties()); return System.getProperties(); } @RestMethod( name="GET", path="/{propertyName}", summary="Get system property", description="Returns the value of the specified system property.", parameters={ @Parameter(in="path", name="propertyName", description="The system property name.") }, responses={ @Response(value=200, description="The system property value, or null if not found.") } ) public String getSystemProperty(@Path String propertyName) throws Throwable { return System.getProperty(propertyName); } @RestMethod( name="PUT", path="/{propertyName}", summary="Replace system property", description="Sets a new value for the specified system property.", guards=AdminGuard.class, parameters={ @Parameter(in="path", name="propertyName", description="The system property name."), @Parameter(in="body", description="The new system property value."), }, responses={ @Response(value=302, headers={ @Parameter(name="Location", description="The root URL of this resource.") } ), @Response(value=403, description="User is not an admin.") } ) public Redirect setSystemProperty(@Path String propertyName, @Body String value) { System.setProperty(propertyName, value); return new Redirect(); } @RestMethod( name="POST", path="/", summary="Add an entire set of system properties", description="Takes in a map of key/value pairs and creates a set of new system properties.", guards=AdminGuard.class, parameters={ @Parameter(in="path", name="propertyName", description="The system property key."), @Parameter(in="body", description="The new system property values.", schema="{example:{key1:'val1',key2:123}}"), }, responses={ @Response(value=302, headers={ @Parameter(name="Location", description="The root URL of this resource.") } ), @Response(value=403, description="Unauthorized: User is not an admin.") } ) public Redirect setSystemProperties(@Body java.util.Properties newProperties) { System.setProperties(newProperties); return new Redirect(); } @RestMethod( name="DELETE", path="/{propertyName}", summary="Delete system property", description="Deletes the specified system property.", guards=AdminGuard.class, parameters={ @Parameter(in="path", name="propertyName", description="The system property name."), }, responses={ @Response(value=302, headers={ @Parameter(name="Location", description="The root URL of this resource.") } ), @Response(value=403, description="Unauthorized: User is not an admin") } ) public Redirect deleteSystemProperty(@Path String propertyName) { System.clearProperty(propertyName); return new Redirect(); } @RestMethod( name="OPTIONS", path="/*", summary="Show resource options", description="Show resource options as a Swagger doc" ) public Swagger getOptions(RestRequest req) { return req.getSwagger(); } }

The resource above is deployed like any other servlet, in this way:

<?xml version="1.0" encoding="UTF-8"?> <web-app version="2.3"> <servlet> <servlet-name>SystemPropertiesService</servlet-name> <servlet-class></servlet-class> </servlet> <servlet-mapping> <servlet-name>SystemPropertiesService</servlet-name> <url-pattern>/systemProperties</url-pattern> </servlet-mapping> </web-app>

Pointing your browser to the resource renders the POJOs as HTML (since that's what the browser specifies in the Accept header).

One of the most useful aspects of using this API is the self-discovering, self-documenting OPTIONS pages. These are constructed automatically using reflection, augmented with information pulled from annotations (as shown above), resource bundles, or Swagger JSON files:

Arbitrarily complex POJO models can be serialized using any of the supported serializers, and content can be parsed using any of the supported parsers.

The juneau-examples-rest project contains various REST resource examples in an easy-to-use REST microservice. One of these is AddressBookResource which serializes AddressBook objects defined below (some code omitted):

/** */ @XmlSchema( prefix="ab", xmlNs={ @XmlNs(prefix="ab", namespaceURI=""), @XmlNs(prefix="per", namespaceURI=""), @XmlNs(prefix="addr", namespaceURI=""), @XmlNs(prefix="mail", namespaceURI="") } ) package org.apache.juneau.examples.addressBook; import org.apache.juneau.xml.annotation.*;   /** Address book bean */ @Bean(typeName="addressBook") public class AddressBook extends LinkedList<Person> {}   /** Person bean */ @Xml(prefix="per") @Bean(typeName="person") public class Person { // Bean properties @Rdf(beanUri=true) public URI uri; public URI addressBookUri; public int id; public String name; @BeanProperty(swap=CalendarSwap.Medium.class) public Calendar birthDate; public LinkedList<Address> addresses; }   /** Address bean */ @Xml(prefix="addr") @Bean(typeName="address") public class Address { // Bean properties @Rdf(beanUri=true) public URI uri; public URI personUri; public int id; @Xml(prefix="mail") public String street, city, state; @Xml(prefix="mail") public int zip; public boolean isCurrent; }

The framework allows you to override header values through GET parameters, so that you can specify the ACCEPT header to see each type. Adding &plainText=true forces the response Content-Type to be text/plain.


Also, localization can be tested by passing in an Accept-Language header.

Simple XML

The Server API is an exhaustive topic on its own. Refer to the additional information for an in-depth examination of the API.

Additional Information

5 - Juneau Client (

The REST client API provides the ability to access remote REST interfaces and transparently convert the input and output to and from POJOs using any of the provided serializers and parsers.

Built upon the Apache HttpClient libraries, it extends that API and provides specialized APIs for working with REST interfaces while maintaining all the functionality available in the HttpClient API.

// Create a reusable JSON client. RestClient client = new RestClientBuilder().build(); // The address of the root resource. String url = "http://localhost:9080/sample/addressBook"; // Do a REST GET against a remote REST interface and convert // the response to an unstructured ObjectMap object. ObjectMap m1 = client.doGet(url).getResponse(ObjectMap.class); // Same as above, except parse the JSON as a bean. AddressBook a2 = client.doGet(url).getResponse(AddressBook.class); // Add a person to the address book. // Use XML as the transport medium. client = new RestClientBuilder(XmlSerializer.class, XmlSerializer.class).build(); Person p = new Person("Joe Smith", 21); int returnCode = client.doPost(url + "/entries", p).run();

The Client API is also an exhaustive topic on its own. Refer to the additional information for an in-depth examination of the API.

Additional Information

6 - Remoteable Services (

Juneau provides the capability of calling methods on POJOs on a server through client-side proxy interfaces. It offers a number of advantages over other similar remote proxy interfaces, such as being much simpler to define and use, and allowing much more flexibility in the types of objects serialized.

The remote proxy interface API allows you to invoke server-side POJO methods on the client side using REST as the communications protocol:

// Create a client with basic JSON support. RestClient client = new RestClientBuilder().rootUrl("http://localhost/remoteable").build(); // Get an interface proxy. IAddressBook ab = client.getRemoteableProxy(IAddressBook.class); // Invoke a method on the server side and get the returned result. Person p = ab.createPerson( new Person( "John Smith", "Aug 1, 1999", new Address("My street", "My city", "My state", 12345, true) ) );

Under the covers, this method call gets converted to a REST POST.

HTTP POST http://localhost/remoteable/ Accept: application/json Content-Type: application/json [ { "name":"John Smith", "birthDate":"Aug 1, 1999", "addresses":[ { "street":"My street", "city":"My city", "state":"My state", "zip":12345, "isCurrent":true } ] } ]

Note that the body of the request is an array. This array contains the serialized arguments of the method. The object returned by the method is then serialized as the body of the response.

To define a remoteable interface, simply add the @Remoteable annotation to your interface class.

@Remoteable public interface IAddressBook {...}

This annotation tells the framework that all methods defined on this interface can be executed remotely. It can be applied to super-interfaces, super-classes, etc..., and exposes the methods at whatever level it is defined.

The @RemoteMethod annotation can also be used on individual methods to tailor which methods are exposed or their paths.

There are two ways to expose remoteable proxies on the server side:

  1. Extending from RemoteableServlet.
  2. Using a @RestMethod(name="PROXY") annotation on a Java method.

The RemoteableServlet class is a simple specialized servlet with an abstract getServiceMap() method to define the server-side POJOs:

@RestResource( path="/remote" ) public class SampleRemoteableServlet extends RemoteableServlet { // Our server-side POJO. AddressBook addressBook = new AddressBook(); @Override /* RemoteableServlet */ protected Map<Class<?>,Object> getServiceMap() throws Exception { Map<Class<?>,Object> m = new LinkedHashMap<Class<?>,Object>(); // In this simplified example, we expose the same POJO service under two different interfaces. // One is IAddressBook which only exposes methods defined on that interface, and // the other is AddressBook itself which exposes all methods defined on the class itself (dangerous!). m.put(IAddressBook.class, addressBook); m.put(AddressBook.class, addressBook); return m; } }

The @RestMethod(name="PROXY") approach is easier if you only have a single interface you want to expose. You simply define a Java method whose return type is an interface, and return the implementation of that interface:

// Our exposed proxy object. @RestMethod(name="PROXY", path="/addressbookproxy/*") public IAddressBook getProxy() { return addressBook; }

In either case, the proxy communications layer is pure REST.
Therefore, in cases where the interface classes are not available on the client side, the same method calls can be made through pure REST calls.
This can also aid significantly in debugging, since calls to the remoteable service can be made directly from a browser with no coding involved.

The parameters and return types of the Java methods can be any of the supported serializable and parsable types in POJO Categories.
This ends up being WAY more flexible than other proxy interfaces since Juneau can handle so may POJO types out-of-the-box.
Most of the time you don't even need to modify your existing Java implementation code.

The RemoteableServlet class itself shows how sophisticated REST interfaces can be built on the Juneau RestServlet API using very little code.
The RemoteableServlet class itself consists of only 53 lines of code, yet is a sophisticated discoverable and self-documenting REST interface.
And since the remote proxy API is built on top of REST, it can be debugged using just a browser.

The requirements for a method to be callable through a remoteable service are:

  • The method must be public.
  • The parameter and return types must be serializable and parsable. Parameterized types are supported.
  • Methods can throw Throwables with public no-arg or single-arg-string constructors which will be automatically recreated on the client side.
Additional Information

6.1 - Interface proxies against 3rd-party REST interfaces

Remoteable proxies can also be used to define interface proxies against 3rd-party REST interfaces. This is an extremely powerful feature that allows you to quickly define easy-to-use interfaces against virtually any REST interface.

Similar in concept to remoteable services defined above, but in this case we simply define our interface with special annotations that tell us how to convert input and output to HTTP headers, query paramters, form post parameters, or request/response bodies.

@Remoteable public interface MyProxyInterface { @RemoteMethod(httpMethod="POST", path="/method") String doMethod(@Header("E-Tag") UUID etag, @Query("debug") boolean debug, @Body MyPojo pojo); } RestClient client = new RestClientBuilder().build(); MyProxyInterface p = client.getRemoteableProxy(MyProxyInterface.class, "http://hostname/some/rest/interface"); String response = p.doMethod(UUID.generate(), true, new MyPojo());

The Java method arguements can be annotated with any of the following:

The return type of the Java method can be any of the following:

  • void - Don't parse any response.
    Note that the method will still throw a runtime exception if an error HTTP status is returned.
  • Any parsable POJO - The body of the response will be converted to the POJO using the parser defined on the RestClient.
  • HttpResponse - Returns the raw HttpResponse returned by the inner HttpClient.
  • Reader - Returns access to the raw reader of the response.
    Note that if you don't want your response parsed as a POJO, you'll want to get the response reader directly.
  • InputStream - Returns access to the raw input stream of the response.
Additional Information

7 - Juneau Microservices (org.apache.juneau.microservice)

WARNING - The microservice API is still in beta. It may be replaced with an OSGi-based architecture.

The file contains a standalone Eclipse project that can be used to quickly create REST microservices as standalone executable jars without the need of an application server. They start almost instantly and are started through a simple java command:

java -jar microservice.jar

When you execute this command, you can point your browser to http://localhost:10000 to bring up the REST interface:

Microservices combine all the functionality of the core, server, and client APIs to provide truly powerful and easy-to-use REST interfaces with minimal overhead.

Additional Information

8 - Samples

The file is a zipped eclipse project that includes everything you need to start the Samples REST microservice in an Eclipse workspace.

This project is packaged as a Juneau Microservice project that allows REST resources to be started using embedded Jetty.

8.1 - Installing in Eclipse

Follow these instructions to create the Samples project in Eclipse:

  1. Download the latest microservice-samples-project .zip file (e.g.
  2. In your Eclipse workspace, go to File->Import->General->Existing Projects into Workspace and click Next.

  3. Select the .zip file and click Finish.

  4. In your workspace, you can now see the following project:

The important elements in this project are:

  • META-INF/MANIFEST.MF - The manifest file.
    This defines the entry point, classpath, top-level REST resources, and location of external configuration file.

    Manifest-Version: 1.0 Main-Class: org.apache.juneau.microservice.RestMicroservice Rest-Resources: Main-ConfigFile: examples.cfg Class-Path: lib/commons-codec-1.9.jar lib/commons-io-1.2.jar lib/commons-logging-1.1.1.jar lib/httpclient-4.5.jar lib/httpcore-4.4.1.jar lib/httpmime-4.5.jar lib/javax.servlet-api-3.0.jar lib/jetty-all-8.1.0.jar lib/juneau-all-5.2.jar lib/org.apache.commons.fileupload_1.3.1.jar lib/derby.jar lib/jena-core-2.7.1.jar lib/jena-iri-0.9.2.jar lib/log4j-1.2.16.jar lib/slf4j-api-1.6.4.jar lib/slf4j-log4j12-1.6.4.jar

  • - The application class.
    This is a specialized microservice in Juneau for exposing REST servlets.
    Allows REST servlets to be registered in the manifest or configuration file.
  • - The top-level REST resource.
    This class serves as a "router" page to child resources:
  • examples.cfg - The external configuration file.
    A deceptively simple yet powerful INI-style configuration file:

    #================================================================================ # Basic configuration file for SaaS microservices # Subprojects can use this as a starting point. #================================================================================ #================================================================================ # REST settings #================================================================================ [REST] # The HTTP port number to use. # Default is Rest-Port setting in manifest file, or 8000. port = 10000 ...

At this point you're ready to start the microservice from your workspace.

8.2 - Running in Eclipse

The microservice-samples-project.launch file is already provided to allow you to quickly start the Samples microservice.

Go to Run->Run Configurations->Java Application->microservice-samples.project and click Run.

In your console view, you can see the following output:

Now open your browser and point to http://localhost:10000. You can see the following:

You have now started a REST interface on port 10000.

8.3 - Building and Running from Command-Line

The build.xml file is a very basic ANT script for building the Samples microservice into an executable jar.

To build the Samples microservice, right-click build.xml and select Run As->Ant Build. Once complete (which takes approximately 1 second), if you refresh the project, you can see the following new directory:

If you open up a command prompt in the build/microservice folder, you can start your microservice as follows:

  • If you get an error message saying Address already in use, this means that the microservice is already running elsewhere, so it cannot bind to port 10000.


The META-INF/MANIFEST.MF file is used to describe the microservice. If you open it, you'll see the following:

Manifest-Version: 1.0 Main-Class: org.apache.juneau.microservice.RestMicroservice Rest-Resources: Main-ConfigFile: examples.cfg Class-Path: lib/commons-codec-1.9.jar lib/commons-io-1.2.jar lib/commons-logging-1.1.1.jar lib/httpclient-4.5.jar lib/httpcore-4.4.1.jar lib/httpmime-4.5.jar lib/javax.servlet-api-3.0.jar lib/jetty-all-8.1.0.jar lib/juneau-all-5.2.jar lib/org.apache.commons.fileupload_1.3.1.jar lib/derby.jar lib/jena-core-2.7.1.jar lib/jena-iri-0.9.2.jar lib/log4j-1.2.16.jar lib/slf4j-api-1.6.4.jar lib/slf4j-log4j12-1.6.4.jar

  • The Main-Class entry is just the standard manifest entry describing the entry point for the executable jar. The org.apache.juneau.microservice.RestMicroservice class is the standard microservice class for REST microservices. Other kinds of microservices can be created by extending the Microservice class.
  • The Rest-Resources entry is a comma-delimited list of REST resources. These are classes that subclass from RestServlet. This is a specialized entry used by org.apache.juneau.microservice.RestMicroservice. In this case, you're pointing to a resource defined in our project,, which serves as a "grouping" page for several other REST resources.
  • The Main-ConfigFile entry points to the location of an external configuration file for our microservice.
  • The Class-Path entry again is just the standard manifest file entry. However, if you need to add extra libraries to your microservice, you'll need to copy them into your lib directory and add them to the classpath here.
  • If you modify the manifest file and get NoClassDefFoundErrors, ensure that the classpath entries contain trailing spaces.

8.5 - RootResources

The RootResources class is the main page for the REST microservice. It serves as the jumping-off point for the other resources.

The class hierarchy for this class is:

Pointing a browser to the resource shows the following:

The RootResources class can also be defined as a servlet in a web.xml file:

<web-app version='2.3'> <servlet> <servlet-name>RootResources</servlet-name> <servlet-class></servlet-class> </servlet> <servlet-mapping> <servlet-name>RootResources</servlet-name> <url-pattern>/*</url-pattern> </servlet-mapping> </web-app>

The RootResources class consists entirely of annotations:

/** * Sample REST resource showing how to implement a "router" resource page. */ @RestResource( path="/", messages="nls/RootResources", htmldoc=@HtmlDoc( links="{options:'?method=OPTIONS'}" ), children={ HelloWorldResource.class, MethodExampleResource.class, RequestEchoResource.class, TempDirResource.class, AddressBookResource.class, SampleRemoteableServlet.class, PhotosResource.class, AtomFeedResource.class, JsonSchemaResource.class, SqlQueryResource.class, TumblrParserResource.class, CodeFormatterResource.class, UrlEncodedFormResource.class, SourceResource.class, ConfigResource.class, LogsResource.class, DockerRegistryResource.class, ShutdownResource.class } ) public class RootResources extends ResourceGroup { private static final long serialVersionUID = 1L; }

The resource bundle contains the localized strings for the resource:

#-------------------------------------------------------------------------------- # RootResources labels #-------------------------------------------------------------------------------- title = Root resources description = This is an example of a router resource that is used to access other resources.

The title and description keys identify the localized values return by the RestRequest.getServletTitle() and RestRequest.getServletDescription() methods.

The children annotation defines the child resources of this router resource. These are resources whose paths are relative to the parent resource.

Child resources must also be subclasses of RestServlet, and must specify a RestResource.path() annotation to identify the subpath of the child. For example, the HelloWorldResource class is annotated as follows:

@RestResource(messages="nls/HelloWorldResource", path="/helloWorld") public class HelloWorldResource extends Resource {

It should be noted that child resources do not need to be defined this way. They could also be defined as servlets in the same way as the root resource. The children annotation approach simply makes it easier to define them without having to touch the web.xml file again. Child resources can also be defined programmatically by using the RestConfig.addChildResources(Class[]) method.

Note that these router pages can be arbitrarily nested deep. You can define many levels of router pages for arbitrarily hierarchical REST interfaces.

  • Let's step back and describe what's going on here:
    During servlet initialization of the RootResources object, the toolkit looks for the @RestResource.children() annotation. If it finds it, it instantiates instances of each class and recursively performs servlet initialization on them. It then associates the child resource with the parent by the name specified by the @RestResource.path() annotation on the child class. When a request for the child URL (/helloWorld) is received, the RootResources servlet gets the request and sees that the URL remainder matches one of its child resources. It then forwards the request to the child resource for processing. The request passed to the child resource is the same as if the child resource had been deployed independently (e.g. path-info, resource-URI, and so forth).

8.6 - HelloWorldResource

The HelloWorldResource class is a simple resource that prints a "Hello world!" message.

/** * Sample REST resource that prints out a simple "Hello world!" message. */ @RestResource( messages="nls/HelloWorldResource", path="/helloWorld", htmldoc=@HtmlDoc( links="{up:'request:/..',options:'servlet:/?method=OPTIONS'}" ) ) public class HelloWorldResource extends Resource { private static final long serialVersionUID = 1L; /** GET request handler */ @RestMethod(name="GET", path="/*") public String sayHello() { return "Hello world!"; } }

#-------------------------------------------------------------------------------- # HelloWorldResource labels #-------------------------------------------------------------------------------- title = Hello World sample resource description = Simplest possible resource sayHello.summary = Responds with "Hello world!"

The class hierarchy for this class is:

Pointing a browser to the resource shows the following:

Using the special &Accept=text/json and &plainText=true parameters allows us to see this page rendered as JSON:

8.7 - MethodExampleResource

The MethodExampleResource class provides examples of the following:

  • Using the Redirect object to perform redirections.
  • Using the various Java method parameter annotations to retrieve request attributes, parameters, etc.
  • Using the annotation programmatic equivalents on the RestRequest object.
  • Setting response POJOs by either returning them or using the RestResponse.setOutput(Object) method.

The resource is provided to show how various HTTP entities (e.g. parameters, headers) can be accessed as either annotated Java parameters, or through methods on the RestRequest object.

/** * Sample REST resource that shows how to define REST methods and OPTIONS pages */ @RestResource( path="/methodExample", messages="nls/MethodExampleResource", htmldoc=@HtmlDoc( links="{up:'request:/..',options:'servlet:/?method=OPTIONS'}" ) ) public class MethodExampleResource extends Resource { private static final long serialVersionUID = 1L; /** Example GET request that redirects to our example method */ @RestMethod(name="GET", path="/") public Redirect doExample() throws Exception { return new Redirect("example1/xxx/123/{0}/xRemainder?q1=123&q2=yyy", UUID.randomUUID()); } /** * Methodology #1 - GET request using annotated attributes. * This approach uses annotated parameters for retrieving input. */ @RestMethod(name="GET", path="/example1/{p1}/{p2}/{p3}/*") public String example1( @Method String method, // HTTP method. @Path String p1, // Path variables. @Path int p2, @Path UUID p3, @Query("q1") int q1, // Query parameters. @Query("q2") String q2, @Query("q3") UUID q3, @PathRemainder String remainder, // Path remainder after pattern match. @Header("Accept-Language") String lang, // Headers. @Header("Accept") String accept, @Header("DNT") int doNotTrack ) { // Send back a simple String response String output = String.format( "method=%s, p1=%s, p2=%d, p3=%s, remainder=%s, q1=%d, q2=%s, q3=%s, lang=%s, accept=%s, dnt=%d", method, p1, p2, p3, remainder, q1, q2, q3, lang, accept, doNotTrack); return output; } /** * Methodology #2 - GET request using methods on RestRequest and RestResponse. * This approach uses low-level request/response objects to perform the same as above. */ @RestMethod(name="GET", path="/example2/{p1}/{p2}/{p3}/*") public String example2( RestRequest req, // A direct subclass of HttpServletRequest. RestResponse res // A direct subclass of HttpServletResponse. ) { // HTTP method. String method = req.getMethod(); // Path variables. RequestPathMatch path = req.getPathMatch(); String p1 = path.get("p1", String.class); int p2 = path.get("p2", int.class); UUID p3 = path.get("p3", UUID.class); // Query parameters. RequestQuery query = req.getQuery(); int q1 = query.get("q1", 0, int.class); String q2 = query.get("q2", String.class); UUID q3 = query.get("q3", UUID.class); // Path remainder after pattern match. String remainder = req.getPathMatch().getRemainder(); // Headers. String lang = req.getHeader("Accept-Language"); String accept = req.getHeader("Accept"); int doNotTrack = req.getHeaders().get("DNT", int.class); // Send back a simple String response String output = String.format( "method=%s, p1=%s, p2=%d, p3=%s, remainder=%s, q1=%d, q2=%s, q3=%s, lang=%s, accept=%s, dnt=%d", method, p1, p2, p3, remainder, q1, q2, q3, lang, accept, doNotTrack); res.setOutput(output); // Or use getWriter(). } /** * Methodology #3 - GET request using special objects. * This approach uses intermediate-level APIs. * The framework recognizes the parameter types and knows how to resolve them. */ @RestMethod(name="GET", path="/example3/{p1}/{p2}/{p3}/*") public String example3( HttpMethod method, // HTTP method. RequestPathMatch path, // Path variables. RequestQuery query, // Query parameters. RequestHeaders headers, // Headers. AcceptLanguage lang, // Specific header classes. Accept accept ) { // Path variables. String p1 = path.get("p1", String.class); int p2 = path.get("p2", int.class); UUID p3 = path.get("p3", UUID.class); // Query parameters. int q1 = query.get("q1", 0, int.class); String q2 = query.get("q2", String.class); UUID q3 = query.get("q3", UUID.class); // Path remainder after pattern match. String remainder = path.getRemainder(); // Headers. int doNotTrack = headers.get("DNT", int.class); // Send back a simple String response String output = String.format( "method=%s, p1=%s, p2=%d, p3=%s, remainder=%s, q1=%d, q2=%s, q3=%s, lang=%s, accept=%s, dnt=%d", method, p1, p2, p3, remainder, q1, q2, q3, lang, accept, doNotTrack); res.setOutput(output); } }

The class consists of 4 methods:

There's a lot going on in this method. Notice how you're able to access URL attributes, parameters, headers, and content as parsed POJOs. All the input parsing is already done by the toolkit. You simply work with the resulting POJOs.

As you might notice, using annotations typically results in fewer lines of code and are therefore usually preferred over the API approach, but both are equally valid.

When you visit this page through the router page, you can see the following (after the automatic redirection occurs):

Notice how the conversion to POJOs is automatically done for us, even for non-standard POJOs such as UUID.

Self-documenting design through Swagger OPTIONS pages

One of the main features of Juneau is that it produces OPTIONS pages for self-documenting design (i.e. REST interfaces that document themselves).

Much of the information populated on the OPTIONS page is determined through reflection. This basic information can be augmented with information defined through:

  • Annotations - An example of this was shown in the SystemPropertiesResource example above.
    Localized strings can be pulled from resource bundles using the $L localization variable.
  • Resource bundle properties - Described in detail in this section.
  • Swagger JSON files with the same name and location as the resource class (e.g. MethodExampleResource.json).
    Localized versions are defined by appending the locale to the file name (e.g. MethodExampleResource_ja_JP.json);

OPTIONS pages are simply serialized Swagger DTO beans. Localized versions of these beans are retrieved using the RestRequest.getSwagger() method.

To define an OPTIONS request handler, the RestServletDefault class defines the following Java method:

/** OPTIONS request handler */ @RestMethod(name="OPTIONS", path="/*") public Swagger getOptions(RestRequest req) { return req.getSwagger(); }

The OPTIONS link that you see on the HTML version of the page is created through a property defined by the HtmlDocSerializer class and specified on the resource class annotation:

@RestResource( htmldoc=@HtmlDoc( links="{options:'?method=OPTIONS'}" ) )

This simply creates a link that's the same URL as the resource URL appended with "?method=OPTIONS", which is a shorthand way that the framework provides of defining overloaded GET requests. Links using relative or absolute URLs can be defined this way.

Metadata about the servlet class is combined with localized strings from a properties file associated through a @RestResource(messages="nls/MethodExampleResources") annotation. The properties file contains localized descriptions for the resource, resource methods, and method parameters.

#-------------------------------------------------------------------------------- # MethodExampleResource labels #-------------------------------------------------------------------------------- title = A simple REST method example resource doGetExample.summary = Sample GET method doGetExample1.summary = Sample GET using annotations doGetExample1.req.path.a1.description = Sample variable doGetExample1.req.path.a2.description = Sample variable doGetExample1.req.path.a3.description = Sample variable doGetExample1.req.query.p1.description = Sample parameter doGetExample1.req.query.p2.description = Sample parameter doGetExample1.req.query.p3.description = Sample parameter doGetExample1.req.header.Accept-Language.description = Sample header doGetExample1.req.header.DNT.description = Sample header doGetExample2.summary = Sample GET using Java APIs doGetExample2.req.path.a1.description = Sample variable doGetExample2.req.path.a2.description = Sample variable doGetExample2.req.path.a3.description = Sample variable doGetExample2.req.query.p1.description = Sample parameter doGetExample2.req.query.p2.description = Sample parameter doGetExample2.req.query.p3.description = Sample parameter doGetExample2.req.header.Accept-Language.description = Sample header doGetExample2.req.header.DNT.description = Sample header getOptions.summary = View these options

Clicking the options link on the page presents you with information about how to use this resource:

This page (like any other) can also be rendered in JSON or XML by using the &Accept URL parameter.

8.8 - UrlEncodedFormResource

The UrlEncodedFormResource class provides examples of the following:

The class is shown below:

/** * Sample REST resource for loading URL-Encoded form posts into POJOs. */ @RestResource( path="/urlEncodedForm", messages="nls/UrlEncodedFormResource" ) public class UrlEncodedFormResource extends Resource { private static final long serialVersionUID = 1L; /** GET request handler */ @RestMethod(name="GET", path="/") public ReaderResource doGet(RestRequest req) throws IOException { return req.getReaderResource("UrlEncodedForm.html", true); } /** POST request handler */ @RestMethod(name="POST", path="/") public Object doPost(@Body FormInputBean input) throws Exception { // Just mirror back the request return input; } public static class FormInputBean { public String aString; public int aNumber; @BeanProperty(pojoSwaps=CalendarSwap.ISO8601DT.class) public Calendar aDate; } }

The RestRequest.getReaderResource(String,boolean) method pulls in the following file located in the same package as the class:


<html> <head> <meta http-equiv="Content-Type" content="text/html;charset=UTF-8"> <style type='text/css'> @import '$R{servletURI}/style.css'; </style> <script type="text/javascript"> // Load results from IFrame into this document. function loadResults(buff) { var doc = buff.contentDocument || buff.contentWindow.document; var buffBody = doc.getElementById('data'); document.getElementById('results').innerHTML = buffBody.innerHTML; } </script> </head> <body> <h3 class='title'>$R{servletTitle}</h3> <h5 class="description">$R{servletDescription}</h5> <div class='data'> <form id='form' action='$R{servletURI}' method='POST' target='buff'> <table> <tr> <th>$L{aString}</th> <td><input name="aString" type="text"></td> </tr> <tr> <th>$L{aNumber}</th> <td><input name="aNumber" type="number"></td> </tr> <tr> <th>$L{aDate}</th> <td><input name="aDate" type="datetime"> (ISO8601, e.g. "<code>2001-07-04T15:30:45Z</code>")</td> </tr> <tr> <td colspan='2' align='right'><button type="submit">$L{submit}</button></td> </tr> </table> </form> <br> <div id='results'> </div> </div> <iframe name='buff' style='display:none' onload="parent.loadResults(this)"></iframe> </body> </html>

The $L variables are string variable that pull in localized values from the resource bundle:

#-------------------------------------------------------------------------------- # UrlEncodedFormResource labels #-------------------------------------------------------------------------------- title = URL-Encoded Form Post Example description = Shows how URL-Encoded form input can be loaded into POJOs. POJO is simply echoed back. aString = A String: aNumber = A Number: aDate = A Date: submit = submit

The $R variables are request string variables. In this case, $R{servletTitle} and $R{servletDescription} resolve to the values returned by RestRequest.getServletTitle() and RestRequest.getServletDescription().

Pointing a browser to the resource shows the following:

Entering some values and clicking submit causes the form bean to be populated and returned back as a POJO response:

Another option is to construct the HTML form in Java using HTML5 beans. This is arguably a better approach since it's typically cleaner with less code, and the headers/links are already part of the page.

import static org.apache.juneau.dto.html5.HtmlBuilder.*; /** GET request handler */ @RestMethod(name="GET", path="/") public Div doGet(RestRequest req) { return div( script("text/javascript", "\n // Load results from IFrame into this document." +"\n function loadResults(buff) {" +"\n var doc = buff.contentDocument || buff.contentWindow.document;" +"\n var buffBody = doc.getElementById('data');" +"\n document.getElementById('results').innerHTML = buffBody.innerHTML;" +"\n }" ), form().id("form").action(req.getServletURI()).method("POST").target("buff").children( table( tr( th(req.getMessage("aString")), td(input().name("aString").type("text")) ), tr( th(req.getMessage("aNumber")), td(input().name("aNumber").type("number")) ), tr( th(req.getMessage("aDate")), td(input().name("aDate").type("datetime"), " (ISO8601, e.g. ", code("2001-07-04T15:30:45Z"), \" )") ), tr( td().colspan(2).style("text-align:right").children( button("submit", req.getMessage("submit")) ) ) ) ), br(), div().id("results"), iframe().name("buff").style("display:none").onload("parent.loadResults(this)") ); }

Additional Information

8.9 - RequestEchoResource

The RequestEchoResource class shows how existing complex POJOs can be serialized to a variety of content types. The example simply takes the incoming HttpServletRequest object and serializes it.

It provides examples of the following:

The class is shown below:

/** * Sample REST resource for echoing HttpServletRequests back to the browser */ @RestResource( path="/echo", messages="nls/RequestEchoResource", htmldoc=@HtmlDoc( links="{up:'request:/..',options:'servlet:/?method=OPTIONS'}", ), properties={ @Property(name=SERIALIZER_maxDepth, value="10"), @Property(name=SERIALIZER_detectRecursions, value="true") }, beanFilters={ // Interpret these as their parent classes, not subclasses HttpServletRequest.class, HttpSession.class, ServletContext.class, }, pojoSwaps={ // Add a special POJO swap for Enumerations EnumerationSwap.class } ) public class RequestEchoResource extends Resource { /** GET request handler */ @RestMethod(name="GET", path="/*", converters={Queryable.class,Traversable.class}) public HttpServletRequest doGet(RestRequest req, RestResponse res, @Properties ObjectMap properties) { // Set the HtmlDocSerializer title programmatically. res.setPageTitle(req.getPathInfo()); // Just echo the request back as the response. return req; } }

Again, there's a lot going on here that's new that requires some explanation. The HttpServletRequest object is not a tree-shaped POJO model. Instead, it contains lots of loops that can cause stack overflow errors if you were to try to serialize it as-is. Also, you want to look only at the properties defined on the HttpServletRequest class, not implementation-specific (i.e. WAS or Jetty) fields which can get messy.

The, @RestResopurce.beanFilters(), and @RestResopurce.pojoSwaps() annotations are used to set behavior properties on the resource's underlying bean context, serializers, and parsers. You're using them here to modify the behavior of serialization for all content types. The annotations are functionally equivalent to using the RestConfig class, as follows:

Hypothetical RequestEchoResource.createSerializers() method

/** Override the default rest serializers to add some transforms */ @Override public synchronize void init(RestConfig config) throws Exception { // Add bean filters for the HttpServletRequest, HttpSession, and ServletContext objects // so that you don't show vendor-specific properties on subclasses. // Add Enumeration POJO swap to be able to render the contents of Enumeration properties. // The max depth and detect recursion options prevent any possible runaway serializations. // This shouldn't happen, but future JEE APIs may introduce deep hierarchies or loops. config .addBeanFilters(HttpServletRequest.class, HttpSession.class, ServletContext.class) .addPojoSwaps(EnumerationSwap.class) .setProperty(SERIALIZER_maxDepth, 10) .setProperty(SERIALIZER_detectRecursions, true) .setPageLinks("{...}"); // Don't forget to call this! super.init(config); }

Note how the annotations generally require fewer lines of code.

Pointing a browser to the resource shows the following:

This gives you an idea of what kinds of POJO models can be serialized, since you are serializing a regular old HttpServletRequest object.

8.10 - AddressBookResource

The AddressBookResource class is a proof-of-concept class that shows a true RESTful API using the Juneau REST toolkit. It provides examples of the following:

  • How to create RESTful interfaces using only POJOs.
  • How to use the @Xml and @XmlSchema annotations to provide XML namespaces and alter how beans are handled by the XML serializer.
  • How to use the @Rdf and @RdfSchema annotations to provide XML namespaces and alter how beans are handled by the Jena serializers.
  • How to use the @BeanProperty annotation to alter how bean properties are handled by the serializers.
  • How to use the annotation to create overloaded methods beyond the standard GET/PUT/POST/DELETE.
  • How to augment data in the OPTIONS page.
  • How to use the RestClient API to interact with the REST resource using the same POJOs used to create the server-side API.
  • How to interact with the REST resource using only a browser.
  • Using the Traversable converter to drill down into POJO models.
  • Using the Queryable converter to provide search/view/sort functionality against POJOs.
  • Using the Introspectable converter to invoke methods on POJOs.
  • Using proxy interfaces.

Pointing a browser to the resource shows the following:

8.10.1 - Classes

The code is straightforward, consisting of the following classes:

  • - Used to define XML namespaces for POJOs in this package.
  • IAddressBook - An interface describing the address book.
  • AddressBook - A data structure consisting of a list of Persons.
  • Person, Address - In-memory representations of people and addresses.
  • CreatePerson, CreateAddress - POJOs for creating and updating people and address through the REST interface.
  • AddressBookResource - The REST resource class.
  • For the sake of brevity, bean properties are defined as public fields instead of the normal getters/setters. Also, the examples are not the most efficient design and are not thread safe.

The file is used to define XML and RDF namespaces on beans and properties in this package. Here you define a default XML and RDF namespaces and URL mappings for namespace shortnames used throughout this package. It should be noted that these features are entirely optional, and there are often several ways of defining these namespaces.

// XML and RDF namespaces used in this package @Xml(ns="ab", namespaces={ @XmlNs(name="ab", uri=""), @XmlNs(name="per", uri=""), @XmlNs(name="addr", uri=""), @XmlNs(name="mail", uri="") } ) @Rdf(ns="ab", namespaces={ @RdfNs(name="ab", uri=""), @RdfNs(name="per", uri=""), @RdfNs(name="addr", uri=""), @RdfNs(name="mail", uri="") } ) package org.apache.juneau.examples.addressBook; import org.apache.juneau.xml.annotation.*;

Our address book uses the following interface:

/** * Interface used to help illustrate proxy interfaces. * See {@link SampleRemoteableServlet}. */ public interface IAddressBook { /** Return all people in the address book */ List<Person> getPeople(); /** Return all addresses in the address book */ List<Address> getAddresses(); /** Create a person in this address book */ Person createPerson(CreatePerson cp) throws Exception; /** Find a person by id */ Person findPerson(int id); /** Find an address by id */ Address findAddress(int id); /** Find a person by address id */ Person findPersonWithAddress(int id); /** Remove a person by id */ Person removePerson(int id); }

  • You interface an interface for our address book so that you can later use it to demonstrate the proxy interface support.

The AddressBook class is our address book. It maintains a list of Person objects with some additional convenience methods:

/** Address book bean */ public class AddressBook extends LinkedList<Person> implements IAddressBook { // The URL of this resource private URI uri; /** Bean constructor - Needed for instantiating on client side */ public AddressBook () {} /** Normal constructor - Needed for instantiating on server side */ public AddressBook (URI uri) {...} @Override /* IAddressBook */ public List<Person> getPeople() { return this; } @Override /* IAddressBook */ public Person createPerson(CreatePerson cp) throws Exception { Person p = new Person(uri, cp); add(p); return p; } @Override /* IAddressBook */ public Person findPerson(int id) { for (Person p : this) if ( == id) return p; return null; } @Override /* IAddressBook */ public Address findAddress(int id) { for (Person p : this) for (Address a : p.addresses) if ( == id) return a; return null; } @Override /* IAddressBook */ public Person findPersonWithAddress(int id) { for (Person p : this) for (Address a : p.addresses) if ( == id) return p; return null; } @Override /* IAddressBook */ public List<Address> getAddresses() { Set<Address> s = new LinkedHashSet<Address>(); for (Person p : this) for (Address a : p.addresses) s.add(a); return new ArrayList<Address>(s); } @Override /* IAddressBook */ public Person removePerson(int id) { Person p = findPerson(id); if (p != null) remove(p); return p; } /** Utility method */ public static Calendar toCalendar(String birthDate) throws Exception { Calendar c = new GregorianCalendar(); c.setTime(DateFormat.getDateInstance(DateFormat.MEDIUM, Locale.US).parse(birthDate)); return c; } }

  • The @Xml(elementName="addressBook") annotation tells the toolkit that when serialized as XML, the element name is <addressBook>. Without this annotation, the element would revert to the generalized <array> tag.
  • The separate constructors are implementation specific and are needed because you're going to be using this class in two ways, since you'll be demonstrating the client code as well as the server code, and it eliminates having to define separate client-side and server-side POJOs:
    1. The normal constructor is used to programmatically create this object in the REST servlet code.
    2. The no-arg constructor is used by the Juneau parsers to construct this object in our client side code.

The Person bean is defined as follows:

/** Person bean */ @Xml(ns="per") @Rdf(prefix="per") @Bean(typeName="person") public class Person { private static int nextPersonId = 1; // Bean properties. @Rdf(beanUri=true) public URI uri; public URI addressBookUri; public String id; public String name; @BeanProperty(swap=CalendarSwap.Medium.class) public Calendar birthDate; public LinkedList<Address> addresses = new LinkedList<Address>(); /** Bean constructor - Needed for instantiating on server side */ public Person() {} /** Normal constructor - Needed for instantiating on client side */ public Person(URI addressBookUri, CreatePerson cp) throws Exception { = nextPersonId++; this.addressBookUri = addressBookUri; if (addressBookUri != null) this.uri = addressBookUri.resolve("people/" + id); =; this.birthDate = cp.birthDate; for (CreateAddress ca : cp.addresses) this.addresses.add(new Address(addressBookUri, uri, ca)); } /** Extra read-only bean property */ public int getAge() { return new GregorianCalendar().get(Calendar.YEAR) - birthDate.get(Calendar.YEAR); } /** Convenience method - Add an address for this person */ public Address createAddress(CreateAddress ca) throws Exception { Address a = new Address(addressBookUri, uri, ca); addresses.add(a); return a; } /** Extra method (for method invocation example) */ public String sayHello(String toPerson, int age) { return name + " says hello to " + toPerson + " who is " + age + " years old"; } }

  • The ns="per" annotations override the default "ab" namespace defined on the package. It applies to this class and all properties of this class.
  • The @Rdf(beanUri=true) annotation identifies the uri property as the resource URI for this resource. This property has special meaning for the RDF serializer. The RDF serializer uses this property for the value of the rdf:resource attribute.
  • The @BeanProperty(swap=CalendarSwap.Medium.class) annotation causes the date field to be serialized in the format "MM dd, yyyy". This could have also been specified globally on the resource level through the annotation.

The Address bean is defined as follows:

/** * Address bean */ @Xml(prefix="addr") @Rdf(prefix="addr") @Bean(typeName="address") public class Address { private static int nextAddressId = 1; // Bean properties @Rdf(beanUri=true) public URI uri; public URI personUri; public int id; @Xml(prefix="mail") @Rdf(prefix="mail") public String street, city, state; @Xml(prefix="mail") @Rdf(prefix="mail") public int zip; public boolean isCurrent; /** Bean constructor - Needed for instantiating on client side */ public Address() {} /** Normal constructor - Needed for instantiating on server side */ public Address(URI addressBookUri, URI personUri, CreateAddress ca) throws Exception { = nextAddressId++; if (addressBookUri != null) this.uri = addressBookUri.resolve("addresses/" + id); this.personUri = personUri; this.street = ca.street; =; this.state = ca.state; =; this.isCurrent = ca.isCurrent; } }

  • This class shows how the namespace can be overridden at the property level through the @Xml(ns="mail") annotation.

The CreatePerson bean is used as the input data for creating a person.

/** Bean for creating a new person */ @Xml(ns="per") @Rdf(ns="addr") @Bean(typeName="person") public class CreatePerson { // Bean properties public String name; @BeanProperty(swap=CalendarSwap.Medium.class) public Calendar birthDate; public LinkedList<CreateAddress> addresses; /** Bean constructor - Needed for instantiating on server side */ public CreatePerson() {} /** Normal constructor - Needed for instantiating on client side */ public CreatePerson(String name, Calendar birthDate, CreateAddress...addresses) {...} }

The CreateAddress bean is used as the input data for creating an address.

/** Bean for creating a new address */ @Xml(ns="addr") @Rdf(ns="addr") @Bean(typeName="address") public class CreateAddress { // Bean properties @Xml(ns="mail") @Rdf(ns="mail") public String street, city, state; @Xml(ns="mail") @Rdf(ns="mail") public int zip; public boolean isCurrent; /** Bean constructor -Needed for instantiating on server side */ public CreateAddress() {} /** Normal constructor - Needed for instantiating on client side */ public CreateAddress(String street, String city, String state, int zip, boolean isCurrent) {...} }

The AddressBookResource class is our REST resource class.

/** * Proof-of-concept resource that shows off the capabilities of working with POJO resources. * Consists of an in-memory address book repository. */ @RestResource( path="/addressBook", messages="nls/AddressBookResource", // Links on the HTML rendition page. // "request:/..." URIs are relative to the request URI. // "servlet:/..." URIs are relative to the servlet URI. // "$C{...}" variables are pulled from the config file. htmldoc=@HtmlDoc( links="{up:'request:/..', options:'servlet:/?method=OPTIONS', source:'$C{Source/gitHub}/org/apache/juneau/examples/rest/addressbook/'}" ), // Properties that get applied to all serializers and parsers. properties={ // Allow INIT as a method parameter. @Property(name=REST_allowMethodParam, value="*"), // Use single quotes. @Property(name=SERIALIZER_quoteChar, value="'"), // Make RDF/XML readable. @Property(name=RDF_rdfxml_tab, value="5"), // Make RDF parsable by adding a root node. @Property(name=RDF_addRootProperty, value="true"), // Make URIs absolute so that we can easily reference them on the client side. @Property(name=SERIALIZER_uriResolution, value="ABSOLUTE") // Make the anchor text on URLs be just the path relative to the servlet. @Property(name=HTML_uriAnchorText, value="SERVLET_RELATIVE") }, // Our stylesheet for the HTML rendition. stylesheet="styles/devops.css", // Support GZIP encoding on Accept-Encoding header. encoders=GzipEncoder.class, // Swagger info. contact="{name:'John Smith',email:''}", license="{name:'Apache 2.0',url:''}", version="2.0", termsOfService="You're on your own.", tags="[{name:'Java',description:'Java utility',externalDocs:{description:'Home page',url:''}}]", externalDocs="{description:'Home page',url:''}" ) public class AddressBookResource extends ResourceJena { private static final long serialVersionUID = 1L; // The in-memory address book private AddressBook addressBook; @Override /* Servlet */ public void init() { try { // Create the address book addressBook = new AddressBook("servlet:/")); // Add some people to our address book by default addressBook.createPerson( new CreatePerson( "Barack Obama", toCalendar("Aug 4, 1961"), new CreateAddress("1600 Pennsylvania Ave", "Washington", "DC", 20500, true), new CreateAddress("5046 S Greenwood Ave", "Chicago", "IL", 60615, false) ) ); addressBook.createPerson( new CreatePerson( "George Walker Bush", toCalendar("Jul 6, 1946"), new CreateAddress("43 Prairie Chapel Rd", "Crawford", "TX", 76638, true), new CreateAddress("1600 Pennsylvania Ave", "Washington", "DC", 20500, false) ) ); } catch (Exception e) { throw new RuntimeException(e); } } /** * [GET /] * Get root page. */ @RestMethod(name="GET", path="/", converters=Queryable.class ) public Link[] getRoot() throws Exception { return new Link[] { new Link("people", "people"), new Link("addresses", "addresses") }; } /** * [GET /people/*] * Get all people in the address book. * Traversable transforming enabled to allow nodes in returned POJO tree to be addressed. * Introspectable transforming enabled to allow public methods on the returned object to be invoked. */ @RestMethod(name="GET", path="/people/*", converters={Traversable.class,Queryable.class,Introspectable.class} ) public AddressBook getAllPeople() throws Exception { return addressBook; } /** * [GET /people/{id}/*] * Get a single person by ID. * Traversable transforming enabled to allow nodes in returned POJO tree to be addressed. * Introspectable transforming enabled to allow public methods on the returned object to be invoked. */ @RestMethod(name="GET", path="/people/{id}/*", converters={Traversable.class,Queryable.class,Introspectable.class} ) public Person getPerson(@Path int id) throws Exception { return findPerson(id); } /** * [GET /addresses/*] * Get all addresses in the address book. */ @RestMethod(name="GET", path="/addresses/*", converters={Traversable.class,Queryable.class} ) public List<Address> getAllAddresses() throws Exception { return addressBook.getAddresses(); } /** * [GET /addresses/{id}/*] * Get a single address by ID. */ @RestMethod(name="GET", path="/addresses/{id}/*", converters={Traversable.class,Queryable.class} ) public Address getAddress(@Path int id) throws Exception { return findAddress(id); } /** * [POST /people] * Create a new Person bean. */ @RestMethod(name="POST", path="/people", guards=AdminGuard.class ) public Redirect createPerson(@Body CreatePerson cp) throws Exception { Person p = addressBook.createPerson(cp); return new Redirect("people/{0}",; } /** * [POST /people/{id}/addresses] * Create a new Address bean. */ @RestMethod(name="POST", path="/people/{id}/addresses", guards=AdminGuard.class ) public Redirect createAddress(@Path int id, @Body CreateAddress ca) throws Exception { Person p = findPerson(id); Address a = p.createAddress(ca); return new Redirect("addresses/{0}",; } /** * [DELETE /people/{id}] * Delete a Person bean. */ @RestMethod(name="DELETE", path="/people/{id}", guards=AdminGuard.class, ) public String deletePerson(@Path int id) throws Exception { addressBook.removePerson(id); return "DELETE successful"; } /** * [DELETE /addresses/{id}] * Delete an Address bean. */ @RestMethod(name="DELETE", path="/addresses/{id}", guards=AdminGuard.class ) public String deleteAddress(@Path int addressId) throws Exception { Person p = addressBook.findPersonWithAddress(addressId); if (p == null) throw new RestException(SC_NOT_FOUND, "Person not found"); Address a = findAddress(addressId); p.addresses.remove(a); return "DELETE successful"; } /** * [PUT /people/{id}/*] * Change property on Person bean. */ @RestMethod(name="PUT", path="/people/{id}/*", guards=AdminGuard.class ) public String updatePerson(RestRequest req, @Path int id, @PathRemainder String remainder) throws Exception { try { Person p = findPerson(id); PojoRest r = new PojoRest(p); ClassMeta<?> cm = r.getClassMeta(remainder); Object in = req.getBody().asType(cm); r.put(remainder, in); return "PUT successful"; } catch (Exception e) { throw new RestException(SC_BAD_REQUEST, "PUT unsuccessful").initCause(e); } } /** * [PUT /addresses/{id}/*] * Change property on Address bean. */ @RestMethod(name="PUT", path="/addresses/{id}/*", guards=AdminGuard.class ) public String updateAddress(RestRequest req, @Path int id, @PathRemainder String remainder) throws Exception { try { Address a = findAddress(id); PojoRest r = new PojoRest(a); ClassMeta<?> cm = r.getClassMeta(remainder); Object in = req.getBody().asType(cm); r.put(remainder, in); return "PUT successful"; } catch (Exception e) { throw new RestException(SC_BAD_REQUEST, "PUT unsuccessful").initCause(e); } } /** * [INIT /] * Reinitialize this resource. */ @RestMethod(name="INIT", path="/", guards=AdminGuard.class ) public String doInit() throws Exception { init(); return "OK"; } /** * [GET /cognos] * Get data in Cognos/XML format */ @RestMethod(name="GET", path="/cognos") public DataSet getCognosData() throws Exception { // The Cognos metadata Column[] items = { new Column("name", "xs:String", 255), new Column("age", "xs:int"), new Column("numAddresses", "xs:int") .addPojoSwap( new PojoSwap<Person,Integer>() { @Override /* PojoSwap */ public Integer swap(BeanSession session, Person p) { return p.addresses.size(); } } ) }; return new DataSet(items, addressBook, this.getBeanContext()); } /** * [OPTIONS /*] * View resource options */ @Override /* RestServletJenaDefault */ @RestMethod(name="OPTIONS", path="/*") public Swagger getOptions(RestRequest req) { return req.getSwagger(); } /** Convenience method - Find a person by ID */ private Person findPerson(int id) throws RestException { Person p = addressBook.findPerson(id); if (p == null) throw new RestException(SC_NOT_FOUND, "Person not found"); return p; } /** Convenience method - Find an address by ID */ private Address findAddress(int id) throws RestException { Address a = addressBook.findAddress(id); if (a == null) throw new RestException(SC_NOT_FOUND, "Address not found"); return a; } }

  • The @RestResource.messages() annotation identifies org/apache/juneau/samples/addressbook/nls/ as the resource bundle for localized message for this class.
  • You are setting XML_enableNamespaces to true to enable XML namespaces. By default, XML namespace support is disabled per XmlSerializerContext.XML_enableNamespaces, so you have to explicitly enable it on our serializers.
  • The XML_autoDetectNamespaces setting is needed to get the XML serializer to add xmlns attributes to the root elements. This causes the XML serializer to scan the POJO objects for namespaces in order to populate the root element. There are other ways to do this, such as explicitely specifying the XML_defaultNamespaceUris setting at either the resource or method level, which might be preferred in high-performance environments. However, XML_autoDetectNamespaces produces the simplest code for our example.
  • The updatePerson() and updateAddress() methods use a guard to only allow administrators access. For the sample code, the guard does nothing. It's up to the implementer to decide how to restrict access.
  • The updatePerson() and updateAddress() methods use the PojoRest class to locate and update individual nodes in a POJO tree using the path remainder on the request.
  • The doInit() method shows an example of an overloaded method using the @RestMethod(name="INIT") annotation.
  • The getOptions() method shows the default OPTIONS page augmented with some additional information.

The OPTIONS page uses the servlet resource bundle to specify the labels so that they're globalizable.

title = AddressBook sample resource description = Proof-of-concept resource that shows off the capabilities of working with POJO resources getRoot.summary = Get root page getRoot.description = Jumping off page for top-level Person and Address beans. doInit.summary = Reinitialize this resource doInit.description = Resets the address book to the original contents. doInit.res.200.description = Returns the string "OK" getAllPeople.summary = Get all people in the address book getAllPeople.res.200.description = Returns a serialized List<Person> getAllPeople.res.200.examples = {'text/json':"[\n\t{\n\t\turi:'http://hostname/addressBook/person/1',\n\t\taddressBookUri:'http://localhost/addressBook',\n\t\tid:1,\n\t\tname:'John Smith',\n\t\tbirthDate:'Jan 1, 2000',\n\t\taddresses:[\n\t\t\t{\n\t\t\t\turi:'http://localhost/addressBook/addresses/1',\n\t\t\t\tpersonUri:'http://localhost/addressBook/people/1',\n\t\t\t\tid:1,\n\t\t\t\tstreet:'101 Main St',\n\t\t\t\tcity:'Anywhere',\n\t\t\t\tstate:'NY',\n\t\t\t\tzip:12345,\n\t\t\t\tisCurrent:true\n\t\t\t}\n\t\t]\n\t}\n]"} getPerson.summary = Get a single person by ID = Person ID = integer getPerson.res.200.description = Returns a serialized Person bean getPerson.res.200.examples = {'text/json':"{\n\turi:'http://hostname/addressBook/person/1',\n\taddressBookUri:'http://localhost/addressBook',\n\tid:1,\n\tname:'John Smith',\n\tbirthDate:'Jan 1, 2000',\n\taddresses:[\n\t\t{\n\t\t\turi:'http://localhost/addressBook/addresses/1',\n\t\t\tpersonUri:'http://localhost/addressBook/people/1',\n\t\t\tid:1,\n\t\t\tstreet:'101 Main St',\n\t\t\tcity:'Anywhere',\n\t\t\tstate:'NY',\n\t\t\tzip:12345,\n\t\t\tisCurrent:true\n\t\t}\n\t]\n\}"} getPerson.res.404.description = Person ID not found getAllAddresses.summary = Get all addresses in the address book getAllAddresses.res.200.description = Returns a serialized List<Address> getAllAddresses.res.200.examples = {'text/json':"[\n\t{\n\t\turi:'http://localhost/addressBook/addresses/1',\n\t\tpersonUri:'http://localhost/addressBook/people/1',\n\t\tid:1,\n\t\tstreet:'101 Main St',\n\t\tcity:'Anywhere',\n\t\tstate:'NY',\n\t\tzip:12345,\n\t\tisCurrent:true\n\t}\n]"} getAddress.summary = Get a single address by ID = Address ID = integer getAddress.res.200.description = Returns a serialized Address bean getAddress.res.200.examples = {'text/json':"{\n\turi:'http://localhost/addressBook/addresses/1',\n\tpersonUri:'http://localhost/addressBook/people/1',\n\tid:1,\n\tstreet:'101 Main St',\n\tcity:'Anywhere',\n\tstate:'NY',\n\tzip:12345,\n\tisCurrent:true\n}"} getAddress.res.404.description = Address ID not found createPerson.summary = Create a new Person bean createPerson.req.body.description = Serialized CreatePerson bean createPerson.req.body.schema = {example:"{\n\tname:'John Smith',\n\tbirthDate:'Jan 1, 2000',\n\taddresses:[\n\t\t{\n\t\t\tstreet:'101 Main St',\n\t\t\tcity:'Anywhere',\n\t\t\tstate:'NY',\n\t\t\tzip:12345,\n\t\t\tisCurrent:true\n\t\t}\n\t]\n\}"} createPerson.res.307.header.Location.description = URL of new person createAddress.summary = Create a new Address bean = Person ID = integer createAddress.req.body.schema = {example:"{\n\tstreet:'101 Main St',\n\tcity:'Anywhere',\n\tstate:'NY',\n\tzip:12345,\n\tisCurrent:true\n}"} createAddress.res.307.header.Location.description = URL of new address deletePerson.summary = Delete a Person bean = Person ID = integer deletePerson.res.200.description = Returns the string "DELETE successful" deletePerson.res.404.description = Person ID not found deleteAddress.summary = Delete an Address bean = Address ID deleteAddress.res.200.description = Returns the string "DELETE successful" deleteAddress.res.404.description = Address ID not found updatePerson.summary = Change property on Person bean = Person ID = integer updatePerson.req.body.description = Any object matching the field updatePerson.res.200.description = Returns the string "PUT successful" updatePerson.res.400.description = Invalid object type used updatePerson.res.404.description = Person ID not found updateAddress.summary = Change property on Address bean = Address ID = integer updateAddress.req.body.description = Any object matching the field updateAddress.res.200.description = Returns the string "PUT successful" updateAddress.res.400.description = Invalid object type used updateAddress.res.404.description = Address ID not foundv getOptions.summary = View resource options getCognosData.summary = Get data in Cognos/XML format getCognosData.res.200.description = Returns a serialized DataSet otherNotes = GZip support enabled. Public methods can be invoked by using the &Method URL parameter. 'text/cognos+xml' support available under root resource only

8.10.2 - Demo

Pointing a browser to the resource shows the results of running the getRoot() method:

Clicking the people link shows you the result of running the getAllPeople() method:

Notice how the URI properties automatically became hyperlinks.

Also notice how the dates are formatted as readable strings. This was from the transform you added to the Calendar property.

Let's see what the output looks like in other formats:


Notice how our XML_enableNamespaces and XML_autoDetectNamespaces settings result in namespaces being used.

Also notice how the @BeanProperty(uri=true) annotations caused the uri properties to become XML attributes instead of elements.


Notice how the @BeanProperty(uri=true) annotations are used to identify values for rdf:about values.

Also notice how URI properties are serialized as rdf:resource attributes.

Now lets look at the schema outputs that can be rendered that show information about the POJO classes themselves.

HTML Schema
JSON Schema
XML Schema

Now let's see what else you can do.

Clicking on the first personUri link executes the getPerson() method, which renders a serialized Person object:

Clicking on the OPTIONS link on the page shows you the Swagger doc generated from our annotations and resource bundle properties:

8.10.3 - Traversable

Because you added the Traversable converter to the getPerson method, you can also address child nodes in the POJO model through path remainders:

8.10.4 - Queryable

The Queryable converter on the getAllPeople() method allows us to perform search/view/sort functions against the data structure before serialization:

Show only the name and addresses columns
Show only names that start with 'B*'
Show only entries with age greater than 60

8.10.5 - Introspectable

The Introspectable converter on the getPerson method allows us to invoke public methods on the addressed POJO (in this case, public methods on the String class):

8.10.6 - ClientTest

The ClientTest class is provided to demonstrate how POJOs can be serialized and parsed through the REST interface using the RestClient class.

You'll notice that the class is a standalone executable that can be invoked as a plain Java process.

/** * Sample client code for interacting with AddressBookResource */ public class ClientTest { public static void main(String[] args) { try { System.out.println("Running client test..."); // Create a client to handle XML requests and responses. RestClient client = new RestClientBuilder().build(); RestClient xmlClient = new RestClientBuilder(XmlSerializer.DEFAULT, XmlParser.DEFAULT).build(); String root = "http://localhost:10000/addressBook"; // Get the current contents of the address book AddressBook ab = client.doGet(root + "/people").getResponse(AddressBook.class); System.out.println("Number of entries = " + ab.getPeople().size()); // Same, but use XML as the protocol both ways ab = xmlClient.doGet(root + "/people").getResponse(AddressBook.class); System.out.println("Number of entries = " + ab.getPeople().size()); // Delete the existing entries for (Person p : ab.getPeople()) { String r = client.doDelete(p.uri).getResponse(String.class); System.out.println("Deleted person " + + ", response = " + r); } // Make sure they're gone ab = client.doGet(root + "/people").getResponse(AddressBook.class); System.out.println("Number of entries = " + ab.getPeople().size()); // Add 1st person again CreatePerson cp = new CreatePerson( "Barack Obama", toCalendar("Aug 4, 1961"), new CreateAddress("1600 Pennsylvania Ave", "Washington", "DC", 20500, true), new CreateAddress("5046 S Greenwood Ave", "Chicago", "IL", 60615, false) ); Person p = client.doPost(root + "/people", cp).getResponse(Person.class); System.out.println("Created person " + + ", uri = " + p.uri); // Add 2nd person again, but add addresses separately cp = new CreatePerson( "George Walker Bush", toCalendar("Jul 6, 1946") ); p = client.doPost(root + "/people", cp).getResponse(Person.class); System.out.println("Created person " + + ", uri = " + p.uri); // Add addresses to 2nd person CreateAddress ca = new CreateAddress("43 Prairie Chapel Rd", "Crawford", "TX", 76638, true); Address a = client.doPost(p.uri + "/addresses", ca).getResponse(Address.class); System.out.println("Created address " + a.uri); ca = new CreateAddress("1600 Pennsylvania Ave", "Washington", "DC", 20500, false); a = client.doPost(p.uri + "/addresses", ca).getResponse(Address.class); System.out.println("Created address " + a.uri); // Find 1st person, and change name Person[] pp = client.doGet(root + "/people?q=(name='Barack+Obama')").getResponse(Person[].class); String r = client.doPut(pp[0].uri + "/name", "Barack Hussein Obama").getResponse(String.class); System.out.println("Changed name, response = " + r); p = client.doGet(pp[0].uri).getResponse(Person.class); System.out.println("New name = " +; } catch (Exception e) { e.printStackTrace(); } } // Utility method public static Calendar toCalendar(String birthDate) throws Exception { Calendar c = new GregorianCalendar(); c.setTime(DateFormat.getDateInstance(DateFormat.MEDIUM).parse(birthDate)); return c; } }

The output from running this code is the following:

Running client test... Number of entries = 2 Deleted person Barack Obama, response = DELETE successful Deleted person George Walker Bush, response = DELETE successful Number of entries = 0 Created person Barack Obama, uri = http://localhost:9081/sample/addressBook/people/3 Created person George Walker Bush, uri = http://localhost:9081/sample/addressBook/people/4 Created address http://localhost:9081/sample/addressBook/addresses/7 Created address http://localhost:9081/sample/addressBook/addresses/8 Changed name, response = PUT successful New name = Barack Hussein Obama

8.10.7 - Browser Tips

The Juneau architecture is designed to make it easy to debug REST resources using nothing more than a browser. The same actions done programmatically in the last section can also be done using URLs. By default, you can override the HTTP Method and Content through GET parameters, as shown below:

// Delete the existing entries http://localhost:10000/addressBook/people/1?method=DELETE http://localhost:10000/addressBook/people/2?method=DELETE // Add 1st person again http://localhost:10000/addressBook/people?method=POST&content={name:'Barack Obama',birthDate:'Aug 4, 1961',addresses:[{street:'1600 Pennsylvania Ave',city:'Washington',state:'DC',zip:20500,isCurrent:true},{street:'5046 S Greenwood Ave',city:'Chicago',state:'IL',zip:60615,isCurrent:false}]} // Add 2nd person again http://localhost:10000/addressBook/people?method=POST&content={name:'George Walker Bush',birthDate:'Jul 6, 1946'} http://localhost:10000/addressBook/people/4/addresses?method=POST&content={street:'43 Prairie Chapel Rd',city:'Crawford',state:'TX',zip:76638,isCurrent:true} http://localhost:10000/addressBook/people/4/addresses?method=POST&content={street:'1600 Pennsylvania Ave',city:'Washington',state:'DC',zip:20500,isCurrent:false} // Change name of 1st person http://localhost:10000/addressBook/people/3/name?method=PUT&content="'Barack Hussein Obama'"

The ability to overload methods is enabled through the RestContext.REST_allowMethodParam property.

8.11 - SampleRemoteableServlet

The SampleRemoteableServlet class shows examples of the following:

The RemoteableServlet class has a single abstract method, RemoteableServlet.getServiceMap(), that defines interface keys and POJO values.

The SampleRemoteableServlet exposes the AddressBook bean from the previous example as a service.

@RestResource( path="/remoteable", messages="nls/SampleRemoteableServlet", title="Remoteable Service Proxy API", description="Sample class showing how to use remoteable proxies. The list below are exposed services that can be retrieved using RestClient.getProxyInterface(Class).", htmldoc=@HtmlDoc( links="{up:'request:/..',options:'servlet:/?method=OPTIONS'}" ), properties={ // Allow us to use method=POST from a browser. @Property(name=REST_allowMethodParam, value="*") } ) public class SampleRemoteableServlet extends RemoteableServlet { AddressBook addressBook = new AddressBook(); @Override /* RemoteableServlet */ protected Map<Class<?>,Object> getServiceMap() throws Exception { Map<Class<?>,Object> m = new LinkedHashMap<Class<?>,Object>(); // In this simplified example, you expose the same POJO service under two different interfaces. // One is IAddressBook which only exposes methods defined on that interface, and // the other is AddressBook itself which exposes all methods defined on the class itself. m.put(IAddressBook.class, addressBook); m.put(AddressBook.class, addressBook); return m; } }

Pointing a browser to the resource shows the following:

Clicking the hyperlinks on each shows you the list of methods that can be invoked on that service. Note that the IAddressBook link shows that you can only invoke methods defined on that interface, whereas the AddressBook link shows ALL public methods defined on that class. Since AddressBook extends from LinkedList, you may notice familiar collections framework methods listed.

  • As good practice, you'll want to use interfaces to prevent all public methods from being exposed.

Proxy interfaces are then retrieved using the RestClient.getRemoteableProxy(Class) method.

The client side code for invoking this method is shown below:

// Create a RestClient using JSON for serialization, and point to the server-side remoteable servlet. RestClient client = new RestClientBuilder() .rootUrl("http://localhost:10000/remoteable") .build(); // Create a proxy interface. IAddressBook ab = client.getRemoteableProxy(IAddressBook.class); // Invoke a method on the server side and get the returned result. Person p = ab.createPerson( new CreatePerson("Test Person", AddressBook.toCalendar("Aug 1, 1999"), new CreateAddress("Test street", "Test city", "Test state", 12345, true)) );

Additional Information

8.12 - TempDirResource

The TempDirResource class shows examples of the following:

  • Extending the DirectoryResource class.
  • Using the Apache ServletFileUpload class to handle multi-part form posts.
  • Using a system property string variable.
  • Using RestMatchers.

Pointing a browser to the resource shows the following:

Pointing a browser to the upload link shows a form entry page:

/** * Sample resource that extends DirectoryResource to open up the temp directory as a REST resource. */ @RestResource( path="/tempDir", messages="nls/TempDirResource", htmldoc=@HtmlDoc( links="{up:'request:/..', options:'servlet:/?method=OPTIONS', upload:'servlet:/upload'}" ), properties={ @Property(name="DirectoryResource.rootDir", value="$S{}"), @Property(name="DirectoryResource.allowViews", value="true"), @Property(name="DirectoryResource.allowDeletes", value="true"), @Property(name="DirectoryResource.allowPuts", value="false") }, stylesheet="styles/devops.css" ) public class TempDirResource extends DirectoryResource { private static final long serialVersionUID = 1L; /** * [GET /upload] - Display the form entry page for uploading a file to the temp directory. */ @RestMethod(name="GET", path="/upload") public ReaderResource getUploadPage(RestRequest req) throws IOException { return req.getReaderResource("TempDirUploadPage.html", true); } /** * [POST /upload] - Upload a file as a multipart form post. * Shows how to use the Apache Commons ServletFileUpload class for handling multi-part form posts. */ @RestMethod(name="POST", path="/upload", matchers=TempDirResource.MultipartFormDataMatcher.class) public Redirect uploadFile(RestRequest req) throws Exception { ServletFileUpload upload = new ServletFileUpload(); FileItemIterator iter = upload.getItemIterator(req); while (iter.hasNext()) { FileItemStream item =; if (item.getFieldName().equals("contents")) { File f = new File(getRootDir(), item.getName()); IOPipe.create(item.openStream(), new FileOutputStream(f)).closeOut().run(); } } return new Redirect(); // Redirect to the servlet root. } /** Causes a 404 if POST isn't multipart/form-data */ public static class MultipartFormDataMatcher extends RestMatcher { @Override /* RestMatcher */ public boolean matches(RestRequest req) { String contentType = req.getContentType(); return contentType != null && contentType.startsWith("multipart/form-data"); } } }

#-------------------------------------------------------------------------------- # TempDirResource labels #-------------------------------------------------------------------------------- title = Temp Directory View Service description = View and download files in the '$S{}' directory.

Note how a system property variable can be defined in the properties file.


<html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <style type='text/css'> @import '$R{servletURI}/style.css'; </style> </head> <body> <h3 class='title'>$R{servletTitle}</h3> <h5 class="description">$R{servletDescription}</h5> <div class='data'> <form id='form' action='$R{servletURI}/upload' method='POST' target='buff' enctype="multipart/form-data"> <input name="contents" type="file"><button type="submit">Submit</button> </form> </div> </body> </html>

Note how the HTML file contains localized variables for the servlet label and description.

Additional Information

8.13 - AtomFeedResource

The AtomFeedResource class shows examples of the following:

Pointing a browser to the resource shows the following:

True ATOM feeds require using an Accept:text/xml header:

Other languages, such as JSON are also supported:

/** * Sample resource that shows how to generate ATOM feeds. */ @RestResource( path="/atom", messages="nls/AtomFeedResource", htmldoc=@HtmlDoc( links="{up:'request:/..',options:'servlet:/?method=OPTIONS'}" ), properties={ @Property(name=SERIALIZER_quoteChar, value="'"), @Property(name=RDF_rdfxml_tab, value="5"), @Property(name=RDF_addRootProperty, value="true") }, encoders=GzipEncoder.class ) public class AtomFeedResource extends ResourceJena { private static final long serialVersionUID = 1L; private Feed feed; // The root resource object @Override /* Servlet */ public void init() { try { feed = new Feed() .setTitle(new Text("text", "Juneau ATOM specification")) .setSubTitle(new Text("html", "Decribes <em>stuff</em> about Juneau")) .setUpdated(parseDateTime("2016-01-02T03:04:05Z")) .setId(new Id("")) .addLinks( new Link("alternate", "text/html", "").setHreflang("en"), new Link("self", "application/atom+xml", "") ) .setRights(new Text("Copyright (c) 2016, Apache Foundation")) .setGenerator(new Generator("Juneau").setUri(new URI("")).setVersion("1.0")) .addEntries( new Entry() .setTitle(new Text("Juneau ATOM specification snapshot")) .addLinks( new Link("alternate", "text/html", ""), new Link("enclosure", "audio/mpeg", "").setLength(12345) ) .setId(new Id("")) .setUpdated(parseDateTime("2016-01-02T03:04:05Z")) .setPublished(parseDateTime("2016-01-02T03:04:05Z")) .addAuthors(new Person("James Bognar").setUri(new URI("")).setEmail("")) .addContributors( new Person("Barry M. Caceres") ) .setContent( new Content() .setLang("en") .setBase(new URI("")) .setType("xhtml") .setText("<div xmlns=\"\"><p><i>[Update: Juneau supports ATOM.]</i></p></div>") ) ); } catch (Exception e) { throw new RuntimeException(e); } } /** * GET request handler */ @RestMethod(name="GET", path="/") public Feed getFeed() throws Exception { return feed; } /** * PUT request handler. * Replaces the feed with the specified content, and then mirrors it as the response. */ @RestMethod(name="PUT", path="/") public Feed setFeed( Feed feed) throws Exception { this.feed = feed; return feed; } }

Additional Information

8.14 - DockerRegistryResource

The DockerRegistryResource class shows examples of the following:

Pointing a browser to the resource shows the following:

Clicking the search link provides you with the search results against the Docker registry:

/** * Sample resource that shows how to mirror query results from a Docker registry. */ @RestResource( path="/docker", title="Sample Docker resource", htmldoc=@HtmlDoc( links="{up:'request:/..',options:'servlet:/?method=OPTIONS'}" ) ) public class DockerRegistryResource extends Resource { private static final long serialVersionUID = 1L; // Get registry URL from examples.cfg file. private String registryUrl = getConfig().getString("DockerRegistry/url"); RestClient rc = new RestClientBuilder().build(); /** [GET /] - Show child resources. */ @SuppressWarnings("nls") @RestMethod(name="GET", path="/") public ResourceDescription[] getChildren(RestRequest req) { return new ResourceDescription[] { new ResourceDescription(req, "search", "Search Registry") }; } /** * PUT request handler. * Replaces the feed with the specified content, and then mirrors it as the response. */ @RestMethod(name="GET", path="/search") public QueryResults query(@Query("q") String q) throws Exception { String url = registryUrl + "/search" + (q == null ? "" : "?q=" + q); return rc.doGet(url).getResponse(QueryResults.class); } public static class QueryResults { public int num_results; public String query; public List<DockerImage> results; } public static class DockerImage { public String name, description; } }

The Docker registry URL is specified in the examples.cfg file:


#================================================================================ # DockerRegistryResource properties #================================================================================ [DockerRegistry] url =

Additional Information

8.15 - TumblrParserResource

The TumblrParserResource class shows examples of the following:

Pointing a browser at a Tumblr blog name, such as ibmblr causes a REST call to be make to the Tumblr blog and the results to be parsed:

@RestResource( path="/tumblrParser", messages="nls/TumblrParserResource", title="Tumblr parser service", description="Specify a URL to a Tumblr blog and parse the results.", htmldoc=@HtmlDoc( links="{up:'request:/..',options:'servlet:/?method=OPTIONS'}" ) ) public class TumblrParserResource extends Resource { private static final long serialVersionUID = 1L; @RestMethod(name="GET", path="/") public String getInstructions() throws Exception { return "Append the Tumblr blog name to the URL above (e.g. /tumblrParser/mytumblrblog)"; } @RestMethod(name="GET", path="/{blogName}") public ObjectList parseBlog(@Path String blogName) throws Exception { ObjectList l = new ObjectList(); RestClient rc = new RestClientBuilder().build(); String site = "http://" + blogName + ""; ObjectMap m = rc.doGet(site).getResponse(ObjectMap.class); int postsTotal = m.getInt("posts-total"); for (int i = 0; i < postsTotal; i += 20) { m = rc.doGet(site + "?start=" + i + "&num=20&transform=text").getResponse(ObjectMap.class); ObjectList ol = m.getObjectList("posts"); for (int j = 0; j < ol.size(); j++) { ObjectMap om = ol.getObjectMap(j); String type = om.getString("type"); Entry e = new Entry(); = om.getString("date"); if (type.equals("link")) e.entry = new Link(om.getString("link-text"), om.getString("link-url")); else if (type.equals("audio")) e.entry = new ObjectMap().append("type","audio").append("audio-caption", om.getString("audio-caption")); else if (type.equals("video")) e.entry = new ObjectMap().append("type","video").append("video-caption", om.getString("video-caption")); else if (type.equals("quote")) e.entry = new ObjectMap().append("type","quote").append("quote-source", om.getString("quote-source")).append("quote-text", om.getString("quote-text")); else if (type.equals("regular")) e.entry = om.getString("regular-body"); else if (type.equals("photo")) e.entry = new Img(om.getString("photo-url-250")); else e.entry = new ObjectMap().append("type", type); l.add(e); } } return l; } public static class Entry { public String date; public Object entry; } }

8.16 - PhotosResource

The PhotosResource class shows examples of the following:

  • How to define custom serializers and parsers at the method level. In this case, you define a serializer and parser to handle images.

The resource consists of a simple registry of images with integer IDs.

It is initialized with a single entry, which can be accessed through a GET request.

/** * Sample resource that allows images to be uploaded and retrieved. */ @RestResource( path="/photos", messages="nls/PhotosResource", title="Photo REST service", description="Use a tool like Poster to upload and retrieve jpeg and png images.", htmldoc=@HtmlDoc( links="{options:'?method=OPTIONS'}" ) ) public class PhotosResource extends RestServletDefault { // Our cache of photos private Map<Integer,Photo> photos = new TreeMap<Integer,Photo>(); @Override /* Servlet */ public void init() { try { // Preload an image. InputStream is = getClass().getResourceAsStream("averycutedog.jpg"); BufferedImage image =; Photo photo = new Photo(0, image); photos.put(, photo); } catch (IOException e) { throw new RuntimeException(e); } } /** Bean class for storing photos */ public static class Photo { private int id; BufferedImage image; Photo(int id, BufferedImage image) { = id; this.image = image; } public URI getURI() throws URISyntaxException { return new URI("photos/"+id); } public int getID() { return id; } } /** GET request handler for list of all photos */ @RestMethod(name="GET", path="/") public Collection<Photo> getAllPhotos(RestRequest req, RestResponse res) throws Exception { res.setPageTitle("Photo REST service"); res.setPageText("Use a tool like Poster to upload and retrieve jpeg and png images."); return photos.values(); } /** GET request handler for single photo */ @RestMethod(name="GET", path="/{id}", serializers=ImageSerializer.class) public BufferedImage getPhoto(RestRequest req, @Path int id) throws Exception { Photo p = photos.get(id); if (p == null) throw new RestException(SC_NOT_FOUND, "Photo not found"); return p.image; } /** PUT request handler */ @RestMethod(name="PUT", path="/{id}", parsers=ImageParser.class) public String addPhoto(RestRequest req, @Path int id, @Body BufferedImage image) throws Exception { photos.put(id, new Photo(id, image)); return "OK"; } /** POST request handler */ @RestMethod(name="POST", path="/", parsers=ImageParser.class) public Photo setPhoto(RestRequest req, @Body BufferedImage image) throws Exception { int id = photos.size(); Photo p = new Photo(id, image); photos.put(id, p); return p; } /** DELETE request handler */ @RestMethod(name="DELETE", path="/{id}") public String deletePhoto(RestRequest req, @Path int id) throws Exception { Photo p = photos.remove(id); if (p == null) throw new RestException(SC_NOT_FOUND, "Photo not found"); return "OK"; } /** OPTIONS request handler */ @RestMethod(name="OPTIONS", path="/*") public Swagger getOptions(RestRequest req) { return req.getSwagger(); } /** Serializer for converting images to byte streams */ @Produces("image/png,image/jpeg") public static class ImageSerializer extends OutputStreamSerializer { @Override public void serialize(Object o, OutputStream out, SerializerSession session) throws IOException, SerializeException { RenderedImage image = (RenderedImage)o; String mediaType = ctx.getMediaType(); ImageIO.write(image, mediaType.substring(mediaType.indexOf('/')+1), out); } } /** Parser for converting byte streams to images */ @Consumes("image/png,image/jpeg") public static class ImageParser extends InputStreamParser { @Override public <T> T parse(InputStream in, ClassMeta<T> type, ParserSession session) throws ParseException, IOException { BufferedImage image =; return (T)image; } } }

8.17 - JsonSchemaResource

The JsonSchemaResource class shows examples of the following:

The resource consists of a pre-initialized Schema object. Pointing a browser to the resource shows the following:

For true JSON-Schema, you need to specify the header Accept: text/json:

/** * Sample resource that shows how to serialize JSON-Schema documents. */ @RestResource( path="/jsonSchema", messages="nls/JsonSchemaResource", title="Sample JSON-Schema document", htmldoc=@HtmlDoc( links="{up:'request:/..',options:'servlet:/?method=OPTIONS'}" ) ) public class JsonSchemaResource extends ResourceJena { private static final long serialVersionUID = 1L; private Schema schema; // The schema document @Override /* Servlet */ public void init() { try { schema = new Schema() .setId("") .setSchemaVersionUri("") .setTitle("Example Schema") .setType(JsonType.OBJECT) .addProperties( new SchemaProperty("firstName", JsonType.STRING), new SchemaProperty("lastName", JsonType.STRING), new SchemaProperty("age", JsonType.INTEGER) .setDescription("Age in years") .setMinimum(0) ) .addRequired("firstName", "lastName"); } catch (Exception e) { throw new RuntimeException(e); } } /** GET request handler */ @RestMethod(name="GET", path="/") public Schema getSchema() throws Exception { return schema; } /** * PUT request handler. * Replaces the schema document with the specified content, and then mirrors it as the response. */ @RestMethod(name="PUT", path="/") public Schema setSchema(@Body Schema schema) throws Exception { this.schema = schema; return schema; } }

8.18 - SqlQueryResource

The SqlQueryResource class shows examples of the following:

The example uses embedded Derby to create a database whose name is defined in the external configuration files.

Pointing a browser to the resource shows the following:

Running a query results in the following output:

/** * Sample resource that shows how Juneau can serialize ResultSets. */ @RestResource( path="/sqlQuery", messages="nls/SqlQueryResource", title="SQL query service", description="Executes queries against the local derby '$C{SqlQueryResource/connectionUrl}' database", htmldoc=@HtmlDoc( links="{up:'request:/..',options:'servlet:/?method=OPTIONS'}" ) ) public class SqlQueryResource extends Resource { private static final long serialVersionUID = 1L; private ConfigFile cf = getConfig(); private String driver = cf.getString("SqlQueryResource/driver"); private String connectionUrl = cf.getString("SqlQueryResource/connectionUrl"); private boolean allowUpdates = cf.getBoolean("SqlQueryResource/allowUpdates", false), allowTempUpdates = cf.getBoolean("SqlQueryResource/allowTempUpdates", false), includeRowNums = cf.getBoolean("SqlQueryResource/includeRowNums", false); @Override /* Servlet */ public void init() { try { Class.forName(driver).newInstance(); } catch (Exception e) { throw new RuntimeException(e); } } /** GET request handler - Display the query entry page. */ @RestMethod(name="GET", path="/") public ReaderResource doGet(RestRequest req) throws IOException { return req.getReaderResource("SqlQueryResource.html", true); } /** POST request handler - Execute the query. */ @RestMethod(name="POST", path="/") public List<Object> doPost(@Body PostInput in) throws Exception { List<Object> results = new LinkedList<Object>(); // Don't try to submit empty input. if (StringUtils.isEmpty(in.sql)) return results; if (in.pos < 1 || in.pos > 10000) throw new RestException(SC_BAD_REQUEST, "Invalid value for position. Must be between 1-10000"); if (in.limit < 1 || in.limit > 10000) throw new RestException(SC_BAD_REQUEST, "Invalid value for limit. Must be between 1-10000"); // Create a connection and statement. // If these fails, let the exception transform up as a 500 error. Connection c = DriverManager.getConnection(connectionUrl); c.setAutoCommit(false); Statement st = c.createStatement(); String sql = null; try { for (String s : in.sql.split(";")) { sql = s.trim(); if (! sql.isEmpty()) { Object o = null; if (allowUpdates || (allowTempUpdates && ! sql.matches("(?:i)commit.*"))) { if (st.execute(sql)) { ResultSet rs = st.getResultSet(); o = new ResultSetList(rs, in.pos, in.limit, includeRowNums); } else { o = st.getUpdateCount(); } } else { ResultSet rs = st.executeQuery(sql); o = new ResultSetList(rs, in.pos, in.limit, includeRowNums); } results.add(o); } } if (allowUpdates) c.commit(); else if (allowTempUpdates) c.rollback(); } catch (SQLException e) { c.rollback(); throw new RestException(SC_BAD_REQUEST, "Invalid query: {0}", sql).initCause(e); } finally { c.close(); } return results; } /** The parsed form post */ public static class PostInput { public String sql; public int pos = 1, limit = 100; } }


<html> <head> <style type='text/css'> @import '$R{servletURI}/style.css'; </style> <script> // Quick and dirty function to allow tabs in textarea. function checkTab(e) { if (e.keyCode == 9) { var t =; var ss = t.selectionStart, se = t.selectionEnd; t.value = t.value.slice(0,ss).concat('\t').concat(t.value.slice(ss,t.value.length)); e.preventDefault(); } } // Load results from IFrame into this document. function loadResults(b) { var doc = b.contentDocument || b.contentWindow.document; var data = doc.getElementById('data') || doc.getElementsByTagName('body')[0]; document.getElementById('results').innerHTML = data.innerHTML; } </script> </head> <body> <h3 class='title'>SQL Query API</h3> <div class='data'> <form action='sqlQuery' method='POST' target='buf'> <table> <tr> <th>Position (1-10000):</th> <td><input name='pos' type='number' value='1'></td> <th>Limit (1-10000):</th> <td><input name='limit' type='number' value='100'></td> <td><button type='submit'>Submit</button><button type='reset'>Reset</button></td> </tr> <tr> <td colspan="5"> <textarea name='sql' style='width:100%;height:200px;font-family:Courier;font-size:9pt;' onkeydown='checkTab(event)'></textarea> </td> </tr> </table> </form> <br> <div id='results'> </div> </div> <iframe name='buf' style='display:none' onload="parent.loadResults(this)"></iframe> </body> </html>


#================================================================================ # SqlQueryResource properties #================================================================================ [SqlQueryResource] driver = org.apache.derby.jdbc.EmbeddedDriver connectionUrl = jdbc:derby:C:/testDB;create=true allowTempUpdates = true includeRowNums = true

8.19 - ConfigResource

The ConfigResource class is a reusable resource defined in the org.apache.juneau.microservice API. It provides a REST interface for reading and altering the microservice config file.

Pointing a browser to the resource shows the following:

An edit page is provided for altering the raw config file:

The ConfigFile class is a serializable POJO, which makes the resource relatively straighforward to implement.

/** * Shows contents of the microservice configuration file. */ @RestResource( path="/config", title="Configuration", description="Contents of configuration file.", htmldoc=@HtmlDoc( links="{up:'request:/..', options:'servlet:/?method=OPTIONS', edit:'servlet:/edit'}" ) ) public class ConfigResource extends Resource { private static final long serialVersionUID = 1L; /** * [GET /] - Show contents of config file. * * @return The config file. * @throws Exception */ @RestMethod(name="GET", path="/", description="Show contents of config file.") public ConfigFile getConfigContents() throws Exception { return getConfig(); } /** * [GET /edit] - Show config file edit page. * * @param req The HTTP request. * @return The config file as a reader resource. * @throws Exception */ @RestMethod(name="GET", path="/edit", description="Show config file edit page.") public ReaderResource getConfigEditPage(RestRequest req) throws Exception { // Note that you don't want variables in the config file to be resolved, // so you need to escape any $ characters that you see. req.setAttribute("contents", getConfig().toString().replaceAll("\\$", "\\\\\\$")); return req.getReaderResource("ConfigEdit.html", true); } /** * [GET /{section}] - Show config file section. * * @param section The section name. * @return The config file section. * @throws Exception */ @RestMethod(name="GET", path="/{section}", description="Show config file section.", parameters={ @Parameter(in="path", name="section", description="Section name.") } ) public ObjectMap getConfigSection(@Path("section") String section) throws Exception { return getSection(section); } /** * [GET /{section}/{key}] - Show config file entry. * * @param section The section name. * @param key The section key. * @return The value of the config file entry. * @throws Exception */ @RestMethod(name="GET", path="/{section}/{key}", description="Show config file entry.", parameters={ @Parameter(in="path", name="section", description="Section name."), @Parameter(in="path", name="key", description="Entry name.") } ) public String getConfigEntry(@Path("section") String section, @Path("key") String key) throws Exception { return getSection(section).getString(key); } /** * [POST /] - Sets contents of config file from a FORM post. * * @param contents The new contents of the config file. * @return The new config file contents. * @throws Exception */ @RestMethod(name="POST", path="/", description="Sets contents of config file from a FORM post.", parameters={ @Parameter(in="formData", name="contents", description="New contents in INI file format.") } ) public ConfigFile setConfigContentsFormPost(@FormData("contents") String contents) throws Exception { return setConfigContents(new StringReader(contents)); } /** * [PUT /] - Sets contents of config file. * * @param contents The new contents of the config file. * @return The new config file contents. * @throws Exception */ @RestMethod(name="PUT", path="/", description="Sets contents of config file.", parameters={ @Parameter(in="body", description="New contents in INI file format.") } ) public ConfigFile setConfigContents(@Body Reader contents) throws Exception { ConfigFile cf2 = new ConfigFileBuilder().build().load(contents); return getConfig().merge(cf2).save(); } /** * [PUT /{section}] - Add or overwrite a config file section. * * @param section The section name. * @param contents The new contents of the config file section. * @return The new section. * @throws Exception */ @RestMethod(name="PUT", path="/{section}", description="Add or overwrite a config file section.", parameters={ @Parameter(in="path", name="section", description="Section name."), @Parameter(in="body", description="New contents for section as a simple map with string keys and values.") } ) public ObjectMap setConfigSection(@Path("section") String section, @Body Map<String,String> contents) throws Exception { getConfig().setSection(section, contents); return getSection(section); } /** * [PUT /{section}/{key}] - Add or overwrite a config file entry. * * @param section The section name. * @param key The section key. * @param value The new value. * @return The new value. * @throws Exception */ @RestMethod(name="PUT", path="/{section}/{key}", description="Add or overwrite a config file entry.", parameters={ @Parameter(in="path", name="section", description="Section name."), @Parameter(in="path", name="key", description="Entry name."), @Parameter(in="body", description="New value as a string.") } ) public String setConfigSection(@Path("section") String section, @Path("key") String key, @Body String value) throws Exception { getConfig().put(section, key, value, false); return getSection(section).getString(key); } private ObjectMap getSection(String name) { ObjectMap m = getConfig().getSectionMap(name); if (m == null) throw new RestException(SC_NOT_FOUND, "Section not found."); return m; } }


<html> <head> <meta http-equiv='Content-Type' content='text/html; charset=UTF-8'> <style type='text/css'> @import '$R{servletURI}/style.css'; </style> </head> <body> <h3 class='title'>$R{servletTitle}</h3> <h5 class='description'>Edit config file</h5> <p class='links'><a href='$R{requestParentURI}'>up</a> - <a href='$R{servletURI}?method=OPTIONS'>options</a></p> <form id='form' action='$R{servletURI}' method='POST' enctype='application/x-www-form-urlencoded'> <div class='data'> <table> <tr><td colspan='2' align='right'><button type='submit'>Submit</button><button type='reset'>Reset</button></td></tr> <tr><th colspan='2'>Contents</th></tr> <tr><td colspan='2'><textarea name='contents' rows='40' cols='120' style='white-space: pre; word-wrap: normal; overflow-x: scroll;'>$SA{contents}</textarea></td></tr> </table> </div> </form> </body> </html>

8.20 - LogsResource

The LogsResource class is a reusable resource defined in the org.apache.juneau.microservice API. It provides a REST interface for the log files generated by the microservice.

Pointing a browser to the resource shows the following:

The highlighted links show the contents of the log file with color highlighting:

The parsed links parse the log file and return the entries as serialized POJOs:

9 - Cookbook Examples

9.1 - Core API

TODO topics
  1. Creating generic JSON objects
  2. Defining XML namespaces

9.2 - Server API

9.2.1 - Apply a transform that changes the format of doubles

The RestResource.pojoSwaps() annotation can be used to add POJO swaps to all the serializers and parsers registered with a servlet.

In this example, you define a POJO swap that converts doubles to localized-format strings using the NumberFormat Java class.

@RestResource( pojoSwaps={ MyRestService.DoubleSwap.class } ) public class MyRestService extends JazzDefaultRestResource { private static final NumberFormat FORMAT = NumberFormat.getInstance(); public static class DoubleSwap extends PojoSwap<Double,String> { @Override /* PojoSwap */ public String swap(BeanSession session, Double o) throws SerializeException { return FORMAT.format(o); } }

9.2.2 - Apply transforms to a subset of serializers or parsers

The RestConfig.addSerializers(Class[]) and RestConfig.addParsers(Class[]) methods are the methods that get called during servlet initialization to create the serializer and parser groups. These methods can be overridden to customize individual serializers and parsers in a way that can't be done using annotations.

In this example, you want to apply the swap from the previous example to change the rendered format for doubles. However, in this case, you apply the swao to only the HTML serializer.

@Override public synchronized void init(RestServletConfig config) throws Exception { config.addSerializer(new HtmlSerializerBuilder().pojoSwaps(DoubleSwap.class).build()); super.init(config); }

TODO topics
  1. Packaging as WAR files
  2. Customizing OPTIONS pages
  3. Rendering form entry pages
  4. Using the ZipFileList response handler
  5. Implementing console-output pages in HTML
  6. Using configuration files
  7. Making a bean traversable
  8. Using the Queryable converter
  9. Sending raw output
  10. Retrieving raw input
  11. Accessing request query parameters
  12. Accessing request path variables
  13. Accessing request content
  14. Accessing request header values
  15. Accessing the path pattern remainder
  16. Creating ResourceGroup pages
  17. Using matchers to define multiple Java methods to the same path pattern
  18. Using the Remoteable API
  19. Sending a redirect request
  20. Changing the stylesheet used by the HTML serializer
  21. Using the Introspector API to invoke methods on Java objects through REST calls
  22. Customizing serializers and parsers at the method level
  23. Accessing config file values
  24. Accessing request query parameters on URL-Encoded FORM posts without triggering HTML body to be read
  25. Accessing localized messages
  26. Defining your own response handlers
  27. Guarding access to a servlet or method
  28. Handling servlet initialization errors
  29. Handling exceptions that occur during response processing
  30. Customizing logging
  31. Creating an ATOM feed
  32. Creating a REST API against a file system
  33. Creating a Docker REST API
  34. Creating a REST API for storing and retrieving images
  35. Creating a REST API for echoing requests
  36. Creating a Tumblr REST API
  37. Creating a Cloudant REST API
  38. Using onPreCall() to intercept requests before processing
  39. Using onPostCall() to intercept requests after processing
  40. Creating child resources programmatically
  41. Defining default request headers
  42. Defining default response headers
  43. Defining your own var-resolver variables
  44. Serving up static files inside the /htdocs embedded package
  45. Defining MIME types of files in the /htdocs folder using the createMimitypesFileTypeMap() method
  46. Defining the title and description of a servlet programmatically using getDescription() and getTitle().
  47. Setting properties programmatically using RestServlet.setProperty()
  48. Setting and saving config file properties
  49. Defining your own abstract subclass of RestServlet or RestServletDefault
  50. Adding GZip support
  51. Accessing environment variables in config files

9.3 - Client API

9.4 - Microservice API

10 - Best Practices

  1. Reuse instances of serializers and parsers whenever possible.
    They are designed to be thread safe, and maintain internal caches of bean metadata to increase performance.

  2. The SERIALIZER_detectRecursions option on the Serializer class can cause a performance penalty of around 20%. Therefore, it's recommended that this option be used only when necessary.

  3. In general, JSON serialization and parsing is about 20% faster than XML. JSON is also more compact than XML.

  4. The Parser methods that take in ClassMeta parameters are slightly faster than methods that take in Class or Object parameters, since the latter methods involve hash lookups to resolve to ClassMeta parameters.

11 - Important Document Links

All up-to-date Juneau documentation is stored in Javadocs, especially package-level Javadocs. This index provides links to the best jumping-off points for documentation.


12 - Release Notes

What's new in each release

6.3.0 (TBD)

  • New @Path annotation for specifying path variables on remoteable interfaces.
  • New @RequestBean annotation for specifying beans with remoteable annotations defined on properties.
  • The following annotations (and related methods on RestCall) can now take NameValuePairs and beans as input when using "*" as the name.
    @FormData,@FormDataIfNE, @Query,@QueryIfNE, @Header,@HeaderIfNE,
  • Many code enhancements make to examples to reflect new functionality.
  • All pages now render aside comments to help explain what feature they're trying to explain using the new features that allow you to customize various elements of the page.

6.2.0 (Apr 28, 2017)

Juneau 6.2.0 is a major update.

  • @RestResource annotation can now be applied to any class! You're no longer restricted to subclassing your resources from RestServlet.
    This is a major enhancement in the API. Anything you could do by subclassing from RestServlet should have an equivalent for non-RestServlet classes.
    The only restriction is that the top-level resource must subclass from RestServlet. Child resources do not.

    The majority of code has been split up into two separate classes:
    • RestConfig - A modifiable configuration of a resource. Subclasses from ServletConfig.
    • RestContext - A read-only configuration that's the result of a snapshot of the config.

    The RestServlet class now has the following initialization method that allows you to override the config settings define via annotations: Non-RestServlet classes must have one of the following to allow it to be instantiated:
    • A public T(RestConfig) constructor.
    • A public T() constructor.
    • The parent resource must have a customized RestResourceResolver for instantiating it.

    Non-RestServlet classes can optionally include the following init methods to gain access to the config and context:
    • public init(RestConfig)
    • public init(RestContext)
  • New annotations added to @RestResource to allow non-RestServlet resources to do the same as subclassing directly from RestServlet:
  • New annotations added to @RestResource and @RestMethod to simplify defining page title, text, and links on HTML views:
    • @RestResource.pageTitle()
    • @RestMethod.pageTitle()
    • @RestResource.pageText()
    • @RestMethod.pageText()
    • @RestResource.pageLinks()
    • @RestMethod.pageLinks()

    // Old method @RestResource( properties={ @Property(name=HTMLDOC_title, value="System properties resource"), @Property(name=HTMLDOC_description, value="REST interface for performing CRUD operations on system properties."), @Property(name=HTMLDOC_links, value="{up:'$R{requestParentURI}',options:'?method=OPTIONS'}") } ) // New method @RestResource( pageTitle="System properties resource", pageDescription="REST interface for performing CRUD operations on system properties.", pageLinks="{up:'$R{requestParentURI}',options:'?method=OPTIONS'}" )

    Typically you're going to simply want to use the title and description annotations which apply to both the page title/text and the swagger doc:

    @RestResource( title="System properties resource", description="REST interface for performing CRUD operations on system properties.", pageLinks="{up:'$R{requestParentURI}',options:'?method=OPTIONS'}" )

  • RestResource.stylesheet() can now take in a comma-delimited list of stylesheet paths.
  • StreamResource can now contain multiple sources from a variety of source types (e.g. byte[] arrays, InputStreams, Files, etc...) and is now immutable. It also includes a new StreamResource.Builder class.
  • Simplified remoteable proxies using the @RestMethod(name="PROXY") annotation on REST methods. Used to expose interface proxies without the need for RemoteableServlet.

    // Server side @RestMethod(name="PROXY", path="/myproxy/*") public IAddressBook getProxy() { return addressBook; } // Client side RestClient client = new RestClientBuilder().rootUrl(samplesUrl).build(); IAddressBook ab = client.getRemoteableProxy(IAddressBook.class, "/addressBook/myproxy");

    See for more information.
  • RestRequest.toString() can be called at any time to view the headers and content of the request without affecting functionality. Very useful for debugging.
  • You can now use numeric values in path annotations.
    When using numeric variable names, you don't need to specify the variable name in the @Path annoation:

    @RestMethod(name="GET", path="/myurl/{0}/{1}/{2}/*") public void doGet(RestRequest req, RestResponse res, @Path String foo, @Path int bar, @Path UUID baz) { ... }

  • annotation is now optional. Defaults to "GET".

6.1.0 (Feb 25, 2017)

Juneau 6.1.0 is a major update.

In particular, this release cleans up the BeanContext API to match the PropertyStore/Context/Session paradigm previously used in the serializer and parser APIs. It also makes several improvements to the HTML and XML serialization support and introduces HTML5 DTO beans.

  • RestRequest now passes locale and timezone to serializers/parsers/transforms.
  • RestRequest.getTimeZone() method.
  • Standardized the following methods in RestRequest to remove dependency on ClassMeta objects and eliminate the need for casts:
    • RestRequest.getHeader(String,Class)
    • RestRequest.getHeader(String,Object,Class)
    • RestRequest.getHeader(String,Type,Type...)
    • RestRequest.getQueryParameter(String,Class)
    • RestRequest.getQueryParameter(String,Object,Class)
    • RestRequest.getQueryParameter(String,Type,Type...)
    • RestRequest.getQueryParameter(String,Object,Type,Type...)
    • RestRequest.getQueryParameters(String,Class)
    • RestRequest.getQueryParameters(String,Type,Type...)
    • RestRequest.getFormDataParameter(String,Class)
    • RestRequest.getFormDataParameter(String,Object,Class)
    • RestRequest.getFormDataParameters(String,Class)
    • RestRequest.getFormDataParameter(String,Type,Type...)
    • RestRequest.getFormDataParameters(String,Type,Type...)
    • RestRequest.getPathParameter(String,Class)
    • RestRequest.getPathParameter(String,Type,Type...)
    • RestRequest.getBody(Class)
    • RestRequest.getBody(Type,Type...)
  • New methods on NameValuePairs
  • Fixed issue where whitespace was not added to UON/URL-Encoding output when &plainText=true specified.

6.0.1 (Jan 3, 2017)

Juneau 6.0.1 is a minor update.


6.0.0 (Oct 3, 2016)

Juneau 6.0.0 is a major update.

The major change is rebranding from "Juno" to "Juneau" in preparation for donation to the Apache Foundation.

  • Removed the JazzRestClient class.
  • New method RestClient.setClientVersion(String). (Mar 23, 2016)

Juno is a moderate update.
  • Fixed potential issue in RestClient where the HTTP connection pool could end up exhausted if an error occurred.
  • Improved thread safety on RestClient.
  • New warning message is logged if a RestClient is garbage collected without being closed: "WARNING: RestClient garbage collected before it was finalized." (Dec 30, 2015)

Juno is a major update. Major changes have been made to the microservice architecture and config INI file APIs.

  • Upgraded to use Apache HttpClient 4.5.
  • New classes:
  • Removed Use HTTP Client equivalent.
  • New methods on RestCall:
  • New lifecycle listener methods on RestCallInterceptor:
  • New methods on RestClient:
    • RestClient.setBasicAuth(String,int,String,String)
    • RestClient.logTo(Level,Logger)
    • RestClient.setRootUrl(String)
    • RestClient.enableSSL(SSLOpts)
    • RestClient.enableLaxSSL()
    • RestClient.doCall(HttpMethod,Object,Object)
    • RestClient.createHttpClientBuilder()
  • New passthrough methods on RestClient defined on HttpClientBuilder:
    • RestClient.setRedirectStrategy(RedirectStrategy)
    • RestClient.setDefaultCookieSpecRegistry(Lookup)
    • RestClient.setRequestExecutor(HttpRequestExecutor)
    • RestClient.setSSLHostnameVerifier(HostnameVerifier)
    • RestClient.setPublicSuffixMatcher(PublicSuffixMatcher)
    • RestClient.setSSLContext(SSLContext)
    • RestClient.setSSLSocketFactory(LayeredConnectionSocketFactory)
    • RestClient.setMaxConnTotal(int)
    • RestClient.setMaxConnPerRoute(int)
    • RestClient.setDefaultSocketConfig(SocketConfig)
    • RestClient.setDefaultConnectionConfig(ConnectionConfig)
    • RestClient.setConnectionTimeToLive(long,TimeUnit)
    • RestClient.setConnectionManager(HttpClientConnectionManager)
    • RestClient.setConnectionManagerShared(boolean)
    • RestClient.setConnectionReuseStrategy(ConnectionReuseStrategy)
    • RestClient.setKeepAliveStrategy(ConnectionKeepAliveStrategy)
    • RestClient.setTargetAuthenticationStrategy(AuthenticationStrategy)
    • RestClient.setProxyAuthenticationStrategy(AuthenticationStrategy)
    • RestClient.setUserTokenHandler(UserTokenHandler)
    • RestClient.disableConnectionState()
    • RestClient.setSchemePortResolver(SchemePortResolver)
    • RestClient.setUserAgent(String userAgent)
    • RestClient.setDefaultHeaders(Collection)
    • RestClient.addInterceptorFirst(HttpResponseInterceptor)
    • RestClient.addInterceptorLast(HttpResponseInterceptor)
    • RestClient.addInterceptorFirst(HttpRequestInterceptor)
    • RestClient.addInterceptorLast(HttpRequestInterceptor)
    • RestClient.disableCookieManagement()
    • RestClient.disableContentCompression()
    • RestClient.disableAuthCaching()
    • RestClient.setHttpProcessor(HttpProcessor)
    • RestClient.setRetryHandler(HttpRequestRetryHandler)
    • RestClient.disableAutomaticRetries()
    • RestClient.setProxy(HttpHost)
    • RestClient.setRoutePlanner(HttpRoutePlanner)
    • RestClient.disableRedirectHandling()
    • RestClient.setConnectionBackoffStrategy(ConnectionBackoffStrategy)
    • RestClient.setBackoffManager(BackoffManager)
    • RestClient.setServiceUnavailableRetryStrategy(ServiceUnavailableRetryStrategy)
    • RestClient.setDefaultCookieStore(CookieStore)
    • RestClient.setDefaultCredentialsProvider(CredentialsProvider)
    • RestClient.setDefaultAuthSchemeRegistry(Lookup)
    • RestClient.setContentDecoderRegistry(Map)
    • RestClient.setDefaultRequestConfig(RequestConfig)
    • RestClient.useSystemProperties()
    • RestClient.evictExpiredConnections()
    • RestClient.evictIdleConnections(long,TimeUnit)
  • JazzRestClient now supports OIDC authentication.
  • These classes are now deprecated and will be removed in a future release:
  • New ReaderResource class. Represents the contents of a text file with convenience methods for resolving StringVar variables and adding HTTP response headers. REST Java methods can return instances of these to serialize Readers containing text with StringVarResolver variables in them.
  • New StreamResource class. REST Java methods can return instances of these to serialize OutputStreams.
  • Fixed a bug in the stack trace hash algorithm in RestException.
  • New methods in RestRequest:
  • Changes in RestResponse:
    • Don't set Content-Encoding: identity when no encoding is used. Some clients don't interpret it correctly.
  • New methods in RestServlet:
    • RestServlet.getChildClasses() - Programmatic equivalent to RestResource.children() annotation.
    • RestServlet.shouldLog(HttpServletRequest,HttpServletResponse,RestException)
    • RestServlet.shouldLogStackTrace(HttpServletRequest,HttpServletResponse,RestException)
    • RestServlet.logObjects(Level,String,Object[])
    • RestServlet.resolveStaticFile(String)
    • RestServlet.createStyleSheet()
    • RestServlet.createFavIcon()
    • RestServlet.createStaticFilesMap()
    • RestServlet.getConfigMgr()
  • Removed JsoParser from RestServletDefault and RestServletJenaDefault. These may represent a security risk if not handled correctly, so removed them as a precaution.
  • Removed RestServletProperties.REST_htDocsFolder. Replaced with RestResource.staticFiles().
  • New annotations on RestResource.
  • Eliminated class. Some JAX-RS implementations use code scanning to find providers, so if you were using DefaultJenaProvider, it would pick up JsonProvider as well. It's easy enough to create your own implementation if needed.
  • OPTIONS pages now specify consumes and produces fields instead of accept and contentType which was confusing.
  • Eliminated properties from OPTIONS pages.
  • New ResourceLink.ResourceLink(String,RestRequest,String,Object[]) constructor.
  • New response handlers:
  • New DevOps stylesheet.
  • Servlet initialization and HTTP requests are now logged at FINE level.
  • Added abstract modifier on various RestServlet subclasses to indicate that they're meant to be subclassed.
  • New RestUtils.trimPathInfo(StringBuffer,String,String) method.
  • Completely revamped API.
  • New Microservice class that serves as a generic interface for microservices and their lifecycles.
  • New RestMicroservice class that implements a microservice consisting of a REST interface.
    • REST resources and configuration settings can be defined through either manifest files or config files.
    • Enhanced logging support.
    • Easy-to-configure SSL support.
    • BASIC auth support.
    • Automatic restartability if the config file changes.
  • Eliminated org.apache.juneau.microservice.Main class. This is replaced by the microservice classes defined above.
  • Resource and ResourceGroup classes now support the following new string variables:
    • "$ARG{key,default}"" - Command line arguments.
    • "$MF{key,default}"" - Manifest file entries.
  • CSS stylesheet now configurable through config file entry "REST/stylesheet".
  • New ResourceJena class if you want your REST interface to support RDF.
  • Eliminated the following classes:
    • org.apache.juneau.microservice.RootResource
    • org.apache.juneau.microservice.SampleResource
  • New predefined reusable resources:
    • ConfigResource - REST resource for viewing and editing microservice config file.
    • LogsResource - REST resource for viewing log files.
    • SampleRootResource - Sample REST resource that contains the config and logs resource as children.
    • ShutdownResource - REST resource for stopping the microservice JVM. Useful for testing purposes.
  • Converted to a REST microservice.
  • Look-and-feel changed to IBM DevOps.
Documentation Updates (Sept 5, 2015)

Juno is a moderate update. The biggest improvement is the ability to associate external INI config files with REST servlets using the ConfigFile functionality.

  • Significant API changes to org.apache.juneau.ini API.
    • ConfigFile is now thread safe and can be shared across multiple threads.
    • New ConfigMgr class for managing configuration files.
    • Serializers and parsers can be associated with config files for storing and retrieving POJOs. Default support provided for JSON.
  • New SimpleHtmlWriter class. Can be used for simple HTML DOM construction.
  • New ProcBuilder class for calling external processes.
  • New ObjectMap.remove(Class,String,Object) method.
  • "class='link'" added to links generated by HtmlDocSerializer.
  • New EncoderGroup#append(EncoderGroup) method.
  • New HtmlDocSerializerContext.HTMLDOC_addLinks configuration property.
  • Modified the Parser.createContext(ObjectMap,Method,Object) method. Outer context objects can be passed in to create instances of non-static inner classes.
  • Fixed bug in HtmlStrippedDocSerializer where exception was thrown when trying to serialize primitive arrays.
  • JsonParser now handles parsing JSON boolean/numeric values as strings to bean properties of type boolean or number.
  • UrlEncodingSerializer and UrlEncodingParser now represent arrays and collections as key-value pairs where the keys are numbers (e.g. "?0=foo&1=bar").
  • Various internal improvements to IOPipe.
  • New ReflectionUtils.getResource(Class,String) method.
  • StringUtils.parseNumber(String,Class) now returns zero for empty strings. This affects the way most parsers handle blank values.
  • New juneau-microservice.jar file that encapsulates all 3 juneau jars with code necessary for creating fast and efficent jetty-powered REST microservices.
    Contains the following:
    • Jetty 8.0
    • Apache HttpClient 4.3.5
    • Apache Commons FileUpload 1.3.1
  • Microservice now supports Java 6 (previously required Java 7) (Aug 15, 2015)

Juno is a minor update in terms of core functionality. But it introduces a Microservices project for building REST microservices and docker containers.

  • New RestRequest.getHeaders() method.
  • New RestResponse.getUnbufferedWriter() method.
  • Fixed bug that was preventing x-response-headers parameter from working correctly.
  • Added annotations to the various classes in so that the order of the bean properties are consistent on all JVMs. On IBM JVMs this is unnecessary because the order of the properties as defined in the class are stored in the bytecode. Other JVMs such as OpenJRE do not implement this feature causing the bean properties to be in random order.
  • New ResourceDescription.ResourceDescription(RestRequest,String,String) constructor. (Aug 5, 2015)

Juno is a minor update affecting the server component only.

  • Fixed bug where localized strings weren't resolving when using chained resource bundles.
  • Servlet and method labels and descriptions can now contain embedded string variables.
  • New RestMethod.input() and RestMethod.responses() annotations. These replace the various description annotations added 2 days ago with a simpler design.
  • New methods on RestServlet:
    • RestServlet.getMethodDescription(String,RestRequest) so that subclasses can override the method description in the OPTIONS page.
    • RestServlet.createRequestVarResolver(RestRequest) so that subclasses can override and augment the variable resolver.
    • RestServlet.resolveChild(Class) and RestServlet.replaceChild(RestServlet) classes that allows customized resolution of servlet instances (e.g. if services are defined in OSGi).
  • Reverted the MethodDescription back to since it was being used by someone. (Aug 3, 2015)

Juno is a major update.

  • BeanMap.get(Object) and BeanMap.put(String,Object) now automatically performs filtering if filters are defined on the bean property or bean property class.
    • Deleted the following methods which are now unnecessary:
      • BeanMap.getFiltered(String)
      • BeanMap.putFiltered(String,Object)
      • BeanMapEntry.getFiltered(String)
      • BeanMapEntry.putFiltered(String,Object)
      • BeanMapEntry.putFiltered(String,Object)
      • BeanPropertyMeta.getFiltered()
      • BeanPropertyMeta.setFiltered(Object)
      • BeanPropertyMeta.getTransformedClassMeta()
    • BeanPropertyMeta.getClassMeta() now returns the filtered type of the property.
  • StringVarResolver now has support for chained resolvers.
  • StringVarResolver now resolves variables inside resolved values. i.e. if a resolved variable value itself contains a variable, it now resolves that variable too.
  • Fixed bug where inner interface classes being used in RestResource.filters() were being interpreted as surrogate classes because they have hidden 1-arg constructors due to being inner classes.
  • Fixed bug in MultiSet where exception was being thrown if last set was empty.
  • New ZipFileList class for providing efficiently zipped directories through the REST interface.
  • New RdfProperties.RDF_useXmlNamespaces property.
  • New XmlParserContext.XML_preserveRootElement property.
  • Worked around bug in Sun VM on OS/X where XML parser was throwing an exception when trying to set a reporter.
  • New ZipFileListResponseHandler class.
  • Simplified lables in servlet resource bundles:
    • "[ClassName].ResourceDescription" is now "[ClassName].label".
    • "[ClassName].MethodDescription.[methodName]" is now "[ClassName].[methodName]".
  • Several changes to RestRequest:
    • Added new methods:
    • Behavior changes to HttpServletRequestWrapper.getPathInfo() to follow Servlet specs. Returns null instead of blank for no path info.
    • RestRequest.getPathRemainder() now automatically decodes the path remainder. Use RestRequest.getPathRemainderUndecoded() to get the unencoded path remainder.
    • Bug fixes in RestRequest.getRequestParentURI() when servlet is mapped to "/*".
    • Bug fixes in RestRequest.getServletURI() when servlet is mapped to "/*".
  • New string replacement variables:
  • Added methods RestServlet.getDescription(RestRequest) and RestServlet.getLabel(RestRequest).
  • RestServletDefault and RestServletJenaDefault now provide default HTML titles and descriptions:

    @Property(name=HTMLDOC_title, value="$R{servletTitle}"), @Property(name=HTMLDOC_description, value="$R{servletDescription}")

  • Options pages on RestServletDefault and RestServletJenaDefault now provide default descriptions and back links: and descriptions:

    @Property(name=HTMLDOC_links, value="{back:'$R{servletURI}"), @Property(name=HTMLDOC_description, value="Resource options")

  • New RestServletGroupDefault class.
  • Removed RestServletProperties.REST_trimTrailingUriSlashes and RestServletProperties.REST_pathInfoBlankForNull.
  • New annotations for providing labels and descriptions. Useful if you don't plan on having to support other languages, so you don't want to provide labels in resource bundles.
  • Support for sorting resources by name in ChildResourceDescriptions.
  • Added /tempDir/upload showing how to use ServletFileUpload with multipart form posts. (June 28, 2015)

Juno is a moderate update.

  • New methods on ClassMeta that eliminates language-specific code in the general class metadata.
    • ClassMeta.getXmlMeta()
    • ClassMeta.getJsonMeta()
    • ClassMeta.getHtmlMeta()
    • ClassMeta.getUrlEncodingMeta()
    • ClassMeta.getRdfMeta()
  • New JsonType.ANY enum.
  • New @Html.asPlainText() annotation.
  • New HtmlDocSerializerContext.HTMLDOC_cssImports property.
  • Signifant changes to RDF support.
    • New @Rdf and @RdfSchema annotations. These replace the use of defining namespaced through the XML annotations, and allows XML and RDF to be serialized using different namespaces.
    • Support for serializing arrays/collections as RDF bags, RDF lists, and multi-valued properties.
    • Fixed warning message about "tab" setting when using the N3/Turtle serializers.
  • New SerializerContext.SERIALIZER_sortCollections and SerializerContext.SERIALIZER_sortMaps properties.
  • FindBug fixes.
  • New RestRequest.getServletParentURI() method.
  • New $R{servletParentURI} variable.
  • Removed final modifier from ChildResourceDescriptions.
  • Added source code links to examples. (May 24, 2015)

Juno is a minor update.

  • New properties in SerializerContext:
    1. SerializerContext.SERIALIZER_relativeUriBase
    2. SerializerContext.SERIALIZER_absolutePathUriBase
    These replace the SERIALIZER_uriAuthority and SERIALIZER_uriContext properties.
  • Improvements in CsvSerializer.
  • New properties in RestServletProperties:
    1. REST_defaultCharset
    2. REST_servletURI
    3. REST_relativeServletURI
  • Improvements involving path calculations when servlets deployed outside of a war file with a context root.
  • New methods in RestCall:
    1. RestRequest.getHeader(String,Class)
    2. RestRequest.getHeader(String,Object,Class)
    3. RestRequest.getHeader(String,Type,Type...)
    4. RestRequest.getQueryParameter(String,Class)
    5. RestRequest.getQueryParameter(String,Object,Class)
    6. RestRequest.getQueryParameter(String,Type,Type...)
    7. RestRequest.getQueryParameter(String,Object,Type,Type...)
    8. RestRequest.getQueryParameters(String,Class)
    9. RestRequest.getQueryParameters(String,Type,Type...)
    10. RestRequest.getFormDataParameter(String,Class)
    11. RestRequest.getFormDataParameter(String,Object,Class)
    12. RestRequest.getFormDataParameters(String,Class)
    13. RestRequest.getFormDataParameter(String,Type,Type...)
    14. RestRequest.getFormDataParameters(String,Type,Type...)
    15. RestRequest.getPathParameter(String,Class)
    16. RestRequest.getPathParameter(String,Type,Type...)
    17. RestRequest.getBody(Class)
    18. RestRequest.getBody(Type,Type...) (May 10, 2015)

Juno is a moderate update.

The major addition is support for Remoteable Services, the ability to invoke server-side POJO methods through client-side proxy interfaces.

  • Added a default OPTIONS page to RestServletDefault and RestServletJenaDefault.
  • RestServletProperties.REST_allowMethodParam has been enhanced to allow you to explicitely specify which HTTP methods can be used in the &method parameter.
  • New methods added to RestRequest:
    • RestRequest.getParser()
    • RestRequest.getReaderParser() (Apr 24, 2015)

Juno is a minor update.

  • ClassMeta.newInstance() method can now create new instances of arrays.
  • Arguments passed to Link are now serialized using UrlEncodingSerializer, so arbitrary POJOs can now be passed as arguments.
  • New date filters: org.apache.juneau.transforms.Datefilter.ISO8601DTZP and org.apache.juneau.transforms.Datefilter.SimpleP.
  • New HtmlDocSerializerContext.HTMLDOC_nowrap setting for HtmlDocSerializer class. Adds "* {white-space:nowrap}" to the style header to prevent word wrapping.
  • Fixed bug in UonParser where passing in a blank value on an array or collection type in a form post would cause a ClassCastException. New behavior creates an empty array or Collection.
  • Improved implementation of UrlEncodingSerializer.serializeUrlPart(Object) method.
  • RestConverter API fixed to handle the existence of POJO filters. Introspectable/Queryable/Traversable classes can now work with filtered POJOs.
  • RestResource.messages() annotation can now be defined on super and subclasses so that NLS messages can be defined in multiple resource bundles.
  • Performance improvements in RestServletNls class.
  • Fixed bug where two REST java methods mapped to the same path pattern wasn't triggering an exception when it was supposed to.
  • New RestCall.setRedirectMaxAttempts(int) method to prevent endless redirection loops.
  • New RestCall#setRetryable(int,long,RetryOn) method to automatically retry on failed connection attempts.
  • New RestCallInterceptor.onRetry(RestCall,int,HttpRequest,HttpResponse) method for listening in on retry attempts. (Mar 28, 2015)

Juno is a minor update.

  • Fixed Map.isEmpty() method.
  • Changed behavior on UonParser to not treat '~' characters as escapes unless followed by one of the following characters: ( ) , $ = ~.
  • New class RestCallInterceptor. Allows responses to be inspected and modified before being processed. Replaces RestClientListener class.
  • Minor connection cleanup fixes. (Feb 14, 2015)

Juno is a moderate update.

  • REST method parameters can now be generic types (e.g. @Param("foo") Map<String,Integer> foo). This applies to headers, attributes, and parameters.
  • New @Param.multipart() and @Query.multipart() annotations for handling multi-part GET and POST parameters.
  • GET parameters are now CASE-SENSITIVE per W3C standards.
    • &Content must now be specified as &content.
    • &Method must now be specified as &method.
    • &debug must now be specified as &debug=true.
    • &plainText must now be specified as &plainText=true.
    • &notrace must now be specified as &noTrace=true.
  • Performance improvements around query parameters.
  • New methods on RestRequest for handling multi-part parameters:
    • RestRequest.getParameters(String,Class)
    • RestRequest#getQueryParameters(String,Class)
  • Fixed Jetty issue in RestResponse.setHeader(String,String) where setting the Content-Type through this method was inconsistent with the behavior in WAS/Tomcat.
  • &noTrace=true now prevents any errors from being logged in log file.
  • Workaround for Jetty issue where ServletContext.getContextPath() always ends with "null".
  • RestServletProperties.REST_allowMethodParam is now true by default on all subclasses of RestServletDefault and RestServletJenaDefault.
  • New method RestCall.allowRedirectsOnPosts(boolean).
  • New method RestCall.peekInputStream() allows you to read response bodies without interrupting execution flow.
  • New method Object.toString() now useful for debugging purposes. Shows all request/response headers and bodies.
  • RestCallException now includes HttpResponse object for easier debugging.
  • New method RestClient.addListener(RestClientListener) for registering request/response listeners.
  • New RestClient.setClassLoader(ClassLoader) method.
  • TLS support in JazzRestClient.
Other changes
  • samples.ear and samples.war projects have been replaced with an OSGi bundle with activated servlets in juno.samples. (Dec 23, 2014)

Juno is a moderate update.

  • Fixed major issue that prevented parsing URL-Encoded form posts into POJOs. Calling HttpServlet.getParameter(String) was forcing the underlying servlet code to process the HTTP body itself, preventing the UrlEncodingSerializer class from being able to parse the content. Updated code no longer inadvertantly calls this method.
  • New RestRequest.getQueryParameter(String), RestRequest.hasQueryParameter(String), and RestRequest.hasAnyQueryParameters(String[]) methods that only look for parameters in the URL query string to prevent loading and parsing of URL-Encoded form posts.
  • New @QParam and @HasQParam annotations for accessing query parameters from the URL query string.
  • &plainText parameter can now specify a false value.
  • Removed properties parameters from RestServlet.onPreCall(RestRequest) and RestServlet.onPostCall(RestRequest,RestResponse) methods since the properties are already accessible through RestRequest.getProperties().
  • Added UonSerializer and UonParser to serializer and parser lists on RestServletDefault and RestServletJenaDefault.
  • Moved to Apache HttpClient 4.3 to match Jazz 6.0.
  • Renamed RestResponseEntity to RestRequestEntity.
  • Improved performance on URL-Encoded form posts by serializing directly to output stream instead of serialized to string first.
  • New methods on RestClient class that makes it easier to associate serializer and parser attributes with registered serializer and parser:
    • RestClient#setProperty(String,Object)
    • RestClient#setProperties(ObjectMap)
    • RestClient#addNotBeanClasses(Class[])
    • RestClient.addTransforms(Class[])
    • RestClient#addImplClass(Class,Class)
  • Renamed RestClient.shutdown() to RestClient.close() to mirror change in Apache API.
  • New CodeFormatterResource for quickly formatting Java and XML code samples in Javadocs.
  • New UrlEncodedFormResource for showing how to work with URL-Encoded form posts. (Dec 1, 2014)

Juno is a major update. There weren't very many code changes, but the source has been made a part of Jazz Foundation. This required some restructuring of the project. The project on Jazz Hub will eventually be discontinued. However, the libraries on IBM Community Source will continue to be updated regularly.

  • Project split up into 3 separate bundles:
    • org.apache.juneau - Core serializers and parsers.
    • - REST server component.
    • - REST client component.
  • Code changes to facilitate breaking up bundles:
    • class moved to Link.
    • References to in Encoder class changed to IOException.
  • Changed configuration names for consistency with Jazz Framework.
  • New RestClient.execute(HttpUriRequest) method that allows subclasses to handle their own HTTP request execution.
  • Changes in JazzRestClient to handle introduction of SSO support in v6.
  • &plainText debug feature was broken.
  • Removed double-buffering in RestRequest.
  • Metadata cleanup, Find Bug fixes. (Oct 25, 2014)

Juno is a moderate update, focused primarily on performance improvements.

  • Improved performance on JSON and URL-Encoding parsers by approximately 50% on large data sets.
    • Rewrote ParserReader class to handle it's own buffering. The change allowed several optimizations to be made when dealing with JSON and URL-Encoding text by avoiding char array copies.
    • Added a estimatedSize parameter to the Parser parse methods to optimize buffering when the input size is known beforehand.
  • Revamped the BeanContext API to perform better in multi-threaded environments.
    • Introduced a new BeanPropertyStore class that handles creation of BeanContext objects. This allows BeanContext objects to be considered immutable, and therefore cacheable/reusable by the framework. While this was technically possible to cache these objects beforehand, it relied on a locking mechanism to prevent bean contexts from being modified after being created. The new mechanism is much more straightforward.
  • Modifications to the APIs to make it easier to work with custom Apache HTTP clients.
    • Added overridable RestClient#createHttpClient() to allow customized subclasses to construct customized HTTP clients.
    • Removed the DefaultRestClient class since it's now fully redundant with RestClient.
    • Added RestClient.shutdown() method for cleaning up the internal HTTP client when you're done using a REST client. (Oct 5, 2014)

Juno is a moderate update.

  • Improved error handling.
  • New ParserContext.PARSER_debug and SerializerContext.SERIALIZER_debug. settings for logging additional information for debugging problems.
  • New SerializerContext.SERIALIZER_ignoreRecursions setting for explicitely ignoring recursions when serializing models. Previously, the SERIALIZER_detectRecursions setting did this, but now it simply looks for recursions and throws exceptions when they occur.
  • Improved handling of StackOverflowErrors. When SERIALIZER_detectRecursions is enabled, a useful error message is displayed showing the exact chain of objects that resulted in the stack overflow.
  • Bug fixes in ResultSetList for Oracle and SQL Server.
  • Serializers and parsers can now access HTTP request attributes, parameters, and headers through SerializerContext.getProperties() and ParserContext.getProperties().
  • Removed media-type and encoding attributes from SerializerContext and ParserContext since these are now available through context properties, and are typically not used.
  • XmlParser now accepts application/xml.
  • Improved handling of bean property serialization when multiple matching pojo filters for the bean property class exist.
  • Improved concurrency on BeanContext class.
  • Fixed bug in Traversable that was causing it to be executed even if the servlet extra path info was empty.
  • Fixed bug in Traversable where it was not picking up filters and properties defined on REST Java methods. (Sept 21, 2014)

Juno is a moderate update.

  • Simplified API for PojoSwap. Since it's rarely used, the beanContext parameter was replaced with a PojoSwap#getBeanContext() method on the class.
  • New simplified way of defining POJO filters without needing to extend PojoSwap. See SurrogateSwap for details.
  • New @Html annotation. Will allow the definition of standard XHTML DTOs in future releases. For now, Img is an example of defining an XHTML element using Juno DTOs.
  • JsonParser now ignores trailing ';' characters in input so that it can parse strings of the form "var x = {'foo':'bar'};".
  • New TumblrParserResource in the samples war file showing how to combine the REST client and server APIs into a single resource in order to download Tumblr blogs and convert the response into any supported response content type. (Sept 1, 2014)

Juno is a moderate update.

  • New Redirect class that simplifies performing redirections in REST methods.
  • New pluggable ResponseHandler class and RestResource.responseHandlers() annotation for defining customer response handlers for special kinds of POJOs.
  • New method UrlEncodingSerializer.serializeUrlPart(Object) method.
  • New method RestRequest.getServletURIBuilder() for construcing servlet-based URLs more efficiently.
  • New method RestResponse.getNegotiatedOutputStream() that uses encoders if a match is found, and RestResponse.getOutputStream() that just return the underlying output stream without any modifications.
  • Fixed bug where some properties were not being propagated correctly when using CoreObject.setProperties(ObjectMap) on serializer and parser subclasses.
  • Fixed bug in HtmlSerializer where URL keys in Maps were not being serialized as hyperlinks.
  • Fixed bug in JsonSerializer where "_class" and "items" attributes were not quoted in strict mode when using SERIALIZER_addClassAttrs feature.
  • Fixed bug where Content-Encoding andCharacter-Encoding headers were being set when calling RestResponse.getOutputStream(). These should not be set if interacting with the output streams at a low level.
  • Eliminated various convenience RestResponse.sendRedirect(...) methods due to the introduction of the Redirect class. (Aug 25, 2014)

Juno is a minor update.

  • New RestServlet.getPath() method.
  • New SerializerContext.getJavaMethod() and ParserContext.getJavaMethod() to allow access to REST methods that invoked the serializers or parsers. For example, can be used to access additional annotations on REST methods to perform special handing during serialization or parsing.
  • Better behavior on overriding of filters in BeanContext.addTransforms(Class[]). Previously, adding multiple conflicting filters resulted in random behavior. Now filters are overridden when multiple matching filters are applied.
  • Allow HtmlDocSerializerContext properties to be set via Serializer.setProperty(String,Object). Previously, these could only be defined through override properties (e.g. through REST class and method annotations).
  • Fixed memory leak in XML parser. (Jun 28, 2014)

Juno is a moderate update.

Core API updates
  • Ability to detect and use non-public bean classes, getters/setters, and fields using the following new properties: Removed BeanContext.INCLUDE_BEAN_FIELD_PROPERTIES and BeanContext.INCLUDE_BEAN_METHOD_PROPERTIES properties, since ignoring fields and methods can be accomplished by setting the appropriate properties above to NONE. Also, the @BeanProperty annotation can now be used on non-public fields/getters/setters to override the default behavior defined by the VISIBILITY properties identified above. This is a convenient way of identifying protected or private fields or methods as bean properties. Previously, you could only identify public fields/getters/setters using this annotation.
  • New BeanContext.BEAN_useJavaBeanIntrospector property that lets Juno use the Java bean Introspector class to determine bean properties. In the previous release, the method for determining bean properties was a mixture of Juno-based and Introspector-based. Now it's either pure Juno-based or pure Introspector-based. The result is considerably cleaner code and consistent behavior.
  • New @BeanIgnore annotation. Replaces the previous @BeanProperty(hidden=true) annotation for ignoring bean properties. Can also be used on classes that look like beans so that they're not treated as beans.
  • Support for parsing into non-static member classes. This applies to all parsers.
  • New @Json.wrapperAttr() annotation that automatically wraps beans and objects in a wrapper attribute when serializing to or parsing from JSON.
  • Changed the default ordering of bean properties to be in parent-to-child class order.
  • New readProperty() and writeProperty() methods added to BeanFilter class to allow individualized serialization and parsing behavior on a class-by-class basis.
  • Eliminated previous restriction where bean subtype attributes had to be listed first in JSON objects when using the Bean.subTypeProperty() annotation. The previous behavior was not strictly JSON-compliant since JSON objects are supposed to consist of unordered lists of key/value pairs. While targeted for JSON, the restriction is also lifted for all other parsers.
  • New fluent-style BeanMap.load() methods for initializing bean maps.
  • HtmlDocSerializer will now embed the data portion of the output in a <div id='data'> element to make it easier to extract the data portion of the page in Javascript in browsers.
REST Server API updates
  • New RestRequest.getJavaMethod() method for getting access to the method used to handle a request. Useful for accessing the method name or annotations during requests, such as in calls to RestGuard.guard(RestRequest,RestResponse).
  • Fixed bug when using Jetty where you tried to read text input after a header was written.
  • Added new string variables $A{...} (request attributes) and $P{...} (request parameters) to RestServlet.createRequestVarResolver(RestRequest). (Apr 27, 2014)

Juno is a minor update.

  • Fixed issue preventing &Accept-Language from being used as a GET parameter.
  • Minor XSS vulnerability fix.
  • Empty results on HTML pages now shows "no results" instead of a blank page.
  • Fixed issues preventing REST pages from rendering HTML in newer versions of Internet Explorer.
  • Changed RestServletProperties.REST_allowMethodParam to be disabled by default. (Jan 25, 2014)

Juno is a minor update.

  • Addressed some behavioral differences between Tomcat and WAS.
    • Query parameter lookup is now always case-insensitive (per WAS behavior).
    • Consistent handling of redirect requests (Tomcat and WAS handle relative redirect paths differently).
  • Fixed bug involving incorrect resolution of overlapping URL match patterns.
  • Overall improvements in HTTP request parameter and header value resolution.
  • Made workspace changes so as not to be dependent on the WAS test environment being loaded.
  • Renamed @Remainder annotation to @PathRemainder.
  • Fixed bug involving incorrect calculation of pathInfo on child resources. (Jan 18, 2014)

Juno is a major update.

Major changes
  • Brand new REST client API that uses Apache HttpClient for HTTP communication.
    The new client API is simply a thin layer on top of HttpClient that performs serialization and parsing using Juno parsers, but leaves all the details of the HTTP connection to the Apache code.
    See the package for details.
  • New package and class for performing REST operations against Jazz servers.
    Includes improved support for FORM authentication, and better SSL certificate validation.
  • Completely redesigned URL-Encoding support.
    See org.apache.juneau.urlencoding package for details.
  • Changes to Parser API.
    • Removal of ExtendedReaderParser abstract class and moved methods into ReaderParser class.
    • Removal of DataFormat class from API since it was no longer necessary due to API change above.
    • Removal of ParserStringReader class.
      This was a reader optimized to work with String input.
      However, it could interfere with garbage collection of the original string object.
      Instead, the existing ParserReader was enhanced to work well with String input, and tests show no significant performance differences.
    • New org.apache.juneau.parser.Parser.parse(Object,int,ClassMeta) convenience method added.
Other changes
  • Various new methods added to StringUtils and ClassUtils.
  • Improved support on BeanContext.getClassMetaFromString(String).
    Now supports resolving "long[]", and so forth.
  • ResourceDescription name parameter is now automatically URL-encoded in links.
  • RestRequest now correctly handles cases involving URL-encoded characters in the path info portion of URLs (e.g. http://host/contextRoot/foo%2Fbar).
  • Removed lazy-initialization that required locking in ClassMeta.
  • New BeanContext.setDefaultParser(ReaderParser) method added for specifying a default parser to use in a bean context (used when converting beans to Strings using BeanContext.convertToType(Object,Class). Old behavior simply used the default JSON serializer in these cases.
  • More consistent handling of exceptions across all parsers.
  • Minor changes to RestRequest class.
    • Changed the order of parameters on RestRequest#getParameter(String,Class).
    • Added RestRequest.getMapParameter(String,Class,Class,Class) and RestRequest.getCollectionParameter(String,Class,Class)} methods. (Dec 18, 2013)

Juno is a minor update.

  • Implemented org.apache.juneau.urlencoding.UrlEncodingParser.parseArgs(Reader,int,ClassMeta[]).
  • name parameter of ResourceDescription#ResourceDescription(String,String,String). is now automatically URL-encoded so that the name can contain special characters (e.g. "foo/bar(baz)").
  • Support for URL-matching and path info containing encoded characters (e.g. '/') now supported.
  • Removed some lazy-initialization of bean information in ClassMeta that allowed the removal of some synchronized blocks.
  • Improved support of BeanContext.getClassMetaFromString(String). Now supports primitive arrays such as "long[]" in addition to the previous support for the equivalent "[J".
  • Various new convenience methods added to StringUtils and ClassUtils. (Nov 26, 2013)

Juno is a minor update.

  • RestGuard.guard(RestRequest,RestResponse) now returns a boolean to allow redirects to login pages.
  • Fixed bug in RestServlet where occasional false positive "duplicate method with same name and path" errors were occurring. (Nov 10, 2013)

Juno is a moderate update.

  • New support for runtime-replaced variables in REST resource properties:

    @RestResource( messages="nls/Messages", properties={ @Property(name="label",value="$L{servletTitle}"), // Localized variable in @Property(name="javaVendor",value="$S{java.vendor}"), // System property @Property(name="foo",value="bar"), @Property(name="bar",value="baz"), @Property(name="v1",value="$R{foo}"), // Request variable. value="bar" @Property(name="v2",value="$R{$R{foo}}") // Nested request variable. value="baz" } )

    See RestServlet.createRequestVarResolver(RestRequest) for more information.
  • Eliminated @Property.type annotation which was the old way of specifying NLS variables that got resolved at runtime.
  • New methods on RestRequest:
    • RestRequest.getVarResolver()
    • RestRequest.getServletURI()
    • RestRequest.getRequestParentURI()
  • New methods on RestResponse:
    • RestResponse.sendRedirect(CharSequence)
  • New methods on RestServlet that allow easier customization by subclasses:
    • RestServlet.createConfigFactory()
    • RestServlet.createConverters()
    • RestServlet.createDefaultRequestHeaders()
    • RestServlet.createDefaultResponseHeaders()
    • RestServlet.createEncoders()
    • RestServlet.createFilters()
    • RestServlet.createGuards()
    • RestServlet.createMimetypesFileTypeMap()
    • RestServlet.createParsers()
    • RestServlet.createProperties()
    • RestServlet.createRequestProperties(ObjectMap,RestRequest)
    • RestServlet.createRequestVarResolver(RestRequest)
    • RestServlet.createSerializers()
    • RestServlet.createUrlEncodingParser()
  • Changed RestServletNls to use ResourceDescription/MethodDescription instead of RestResource/RestMethod
  • New property RestServletProperties.REST_htDocsFolder.
    New support for serving up static documents from classpath through REST interface.
  • Exception APIs now use MessageFormat (e.g. "{0}") for message variables instead of "%s".
  • New @Bean.stopClass annotation for specifying stop classes for bean properties.
  • New BeanFilter.setStopClass(Class) which is the program equivalent to the annotation above.
  • New methods on ResultSetList:
    • ResultSetList.handleBlob(Blob)
    • ResultSetList.handleClob(Clob) (Oct 20, 2013)

Juno is a moderate update.

  • Removed generic parameter from WriterSerializer class.
    • Many of the examples in the documentation were written as follows, which resulted in "unchecked" compile warnings:
      WriterSerializer s = new JsonSerializer();
      These compile warnings will now go away.
  • New settings in BeanContext. These can be applied to all serializers/parsers.
  • Eliminated addNotBeanClassPatterns(String...) methods throughout API since these are now controlled by BeanContext.BEAN_notBeanPackages_add / BeanContext.BEAN_notBeanPackages_remove properties.
  • New settings in RestServletProperties.
    • RestServletProperties.REST_trimTrailingUriSlashes
      Also removed RestRequest.getRequestURI(boolean trimTrailingSlashes) method which is now redundant with this property.
    • RestServletProperties.REST_pathInfoBlankForNull
      Also removed RestRequest.getPathInfo(boolean returnBlankForNull) method which is now redundant with this property.
  • New JSON-Schema SchemaMap class for supporting linked schemas.
  • Serializers will no longer throw an exception when maxDepth setting is reached, and will instead simply ignore content below the specified depth.
    While the old behavior was as-designed, the new behavior is more in-line with expected behavior.
  • Added support for HTTP header "X-Response-Headers" to RestServlet.
    Allows you to specify one or more headers that should be returned on the response from the servlet.
    For example, to get a page to automatically refresh every 1 second, you can append the following to a URL: ?x-response-headers={Refresh=1}
  • Removed HtmlDocSerializerContext.HTML_REFRESH setting that added a Refresh meta tag to HTML documents, since this can now be controlled through X-Response-Headers.
  • Small improvements to samples.
    • PhotosResource now includes a default entry. (Oct 5, 2013)

Juno is a moderate update.

  • New support for generating and consuming fully-compliant JSON-Schema documents.
    See org.apache.juneau.dto.jsonschema for information.
  • New methods added to Parser:
    • org.apache.juneau.parser.Parser.parseMap(Object,int,Class,Class,Class)
    • org.apache.juneau.parser.Parser.parseCollection(Object,int,Class,Class)
  • @Bean annotation can now be defined on interfaces and inherited by subclasses.
  • Support for customizing serialized values for Enums through overriding toString() and fromString() on the enum class.
    Previously used Enum.valueOf() to convert strings back into Enums.
    Used for JSON-Schema support to allow JsonType enum to be serialized to lowercase per the specification (e.g. "string" instead of "STRING").
  • Cognos DTOs now have fluent-style bean setters.
  • Support for generic bean objects whose type was erased at compile time.
    Previous behavior gave you an error message that the type could not be determined.
    New behavior assumes a type of Object when the type is erased.
  • Bug fixes:
    • When duplicate fluent-style setters were defined with different parameter types (e.g. setFoo(Foo f), setFoo(Bar b)), the BeanMap API would sometime choose the wrong setter as the bean property setter.
      Now validates that the setter being chosen is the one whose return type matches the property getter.
    • Passing in Accept GET parameters with '+' (e.g. &Accept=text/json+simple) wasn't working anymore.
      The Accept parameter is supposed to interpret spaces as '+' to allow you to not have to write &Accept=text/json%2Bsimple.
    • Parsers would not set bean properties of abstract type Number.
      Now it detects the numeric type based on input and sets the value accordingly. (Aug 9, 2013)

Juno is a moderate update.

  • Simplified the Serializer and Parser class hierarchies.
    This reverses a previous change that added a bunch of interfaces in these APIs (and subsequently required compiling with Java 7 to get around a compiler bug).
    The new class hierarchy is much simpler to understand.
  • Added XMLGregorianCalendarSwap to convert these to ISO8601 strings during serialization, and vice versa during parsing.
  • Added a strict mode to JsonParser.
  • Added default JsonParser.DEFAULT_STRICT parser. (Aug 8, 2013)

Juno is a minor update.

  • Fixed bug involving beans using Bean.subTypes() annotation in addition to subTypes property.
  • Modified the JSON parser to handle non-existent JSON values to get around an issue where Cognos was generating invalid JSON. (Aug 2, 2013)

Juno is a moderate update.

  • Revamped the API for filter support:
    • Updated BeanFilter class to mirror the @Bean annotation.
    • Introduced support for bean Bean.subTypeProperty() subtypes.
    • Replaced @Bean(filter=xxx) with new @Transform annotation.
  • Revamped URL-Encoding support.
    The old URL-Encoding serializer and parser simply used the JSON serializer/parser with a thin URL-encoding top layer.
    The new URL-Encoding serialize and parser was written from scratch and is considerably more consistent in design and output.
  • Improved number parsing.
    The new number parser should handle any valid numeric syntax for decimals and floats that Java itself supports.
  • JsonSerializer LAX mode now quotes reserved word attributes.
  • New predefined DateFilters with millisecond precision:
    • org.apache.juneau.transforms.DateSwap.ISO8601DTP
    • org.apache.juneau.transforms.DateSwap.ISO8601DTZP (July 9, 2013)

Juno is a moderate update.

  • Fixes an OutOfMemoryError and performance issue caused by incorrect caching of class metadata.
  • Added WriterSerializer.serialize(Object,Writer) convenience method for serializing directly to a writer.
    Applies to all serializers. (July 7, 2013)

Juno is a moderate update. (Jun 5, 2013)

Juno is a minor update.

  • FindBug fixes.
  • Changed the way child REST resources are defined.
    Eliminated the @RestChild annotation on getter methods and replaced it with @RestResource.children() defined on the resource class itself.
    Child resource paths are specified through @RestResource.path().
  • New ChildResourceDescriptions bean for automatically generating the contents of router resource pages.
  • Changed @RestMethod.pattern() to @RestMethod.path() for naming consistency. (May 11, 2013)

Juno is a minor update.

Core API updates
  • New ResultSetList DTO for serializing SQL result sets to JSON/XML/HTML and so forth.
  • New SqlQueryResource class in the sample war for demonstrating the ResultSetList DTO.
Server API updates
  • Fixed issue with media type for CSS files being reported as "text/plain" instead of "text/css".
  • Moved initialization of class properties to before the call to Servlet.init() so that getProperties() can be called during servlet initialization.
  • New @Property.type annotation with support for using system properties as resource properties. (May 9, 2013)

Juno is a major update.

Core API updates
  • New support for ATOM.
    • New AtomFeedResource class added to sample war.
  • New XmlFormat.CONTENT enum value.
    Allows bean properties to be persisted as XML element text.
  • New XmlContentHandler class and @Xml.contentHandler annotation.
    Allows customized serialization and parsing of beans to XML element text.
    Added for support of ATOM text content that must support both plain text and embedded XHTML.
  • New @XmlSchema and updated @XmlNs annotations to better mimic JAXB.
  • Removed @Xml.valAttr annotation since it's now redundant with @Xml(format=CONTENT).
  • Fixed timezone bug in CalendarSwap.
  • Simplified Serializer.serialize(Object,Object,SerializerContext) method.
  • Fixed bug where lists returned by ObjectMap.getObjectList(String) were not updatable.
  • Eliminated old RDF/XML serializer.
Documentation updates (Apr 14, 2013)

Juno is a minor update.

  • Simplified Cognos support.
  • Fixed bug where @Xml annotation was not being inherited by inner classes.
  • Javadoc stylesheet improvements. (Apr 12, 2013)

Juno is a minor update.

Core API changes
  • New @Property.nls() annotation for specifying localized property values.
    For example, allows you to set the HTMLDOC_title and HTMLDOC_description properties to localized values pulled from a resource bundle.
    See the AddressBookResource class for an example.
REST Servlet API changes
  • Fix a bug where the &Content query parameter was not always parsed correctly. (Apr 9, 2013)

Juno is a minor update.

Core API changes
Servlet API changes
  • Added new RestServlet.addDefaultProperties(ObjectMap,RestRequest) method for programatically adding properties to the property map per request.
  • Added the following new properties in the properties map to make them easily available to serializers and parsers (since they don't have access to the HTTP request object).
    Note that the SerializerContext.SERIALIZER_uriAuthority and SerializerContext.SERIALIZER_uriContext properties were previously available.
    • RestServletProperties.REST_servletPath
    • RestServletProperties.REST_pathInfo
    • RestServletProperties.REST_method
  • Path variables annotated with @Attr are now automatically URL-decoded. (Apr 7, 2013)

Juno is a major update.

Core API changes
  • New Jena-based RdfSerializer for serializing POJOs to RDF/XML, RDF/XML-ABBREV, N-Triple, Turtle, and N3.
    Serializes ANY POJOs to RDF, even simple objects and primitives.
  • New Jena-based RdfParser for parsing RDF/XML, RDF/XML-ABBREV, N3, Turtle, and N-Triple back into POJOs.
  • XmlSerializerContext.XML_autoDetectNamespaces default changed to true.
    The old default value would cause XML with unmapped namespaces if you didn't manually specify them via the XmlSerializerContext.XML_namespaces annotation.
    While setting the default to true is somewhat slower (since the serializer must crawl the POJO tree to find namespaces), the benefits of having it work out-of-the-box outweighs the performance concerns.
    For developers concerned about performance, they can always change it back to false and specify the namespaces themselves.
REST server API changes
  • Allow inheritance of @RestResource annotation.
    Serializers, parsers, filters, properties , guards, and converters definitions are automatically inherited from parent classes and interfaces.
  • Enhancements to @RestMethod annotation:
    • New RestMethod.filters() annotation for defining POJO filters at the method level.
    • New RestMethod.serializersInherit() and RestMethod.parsersInherit() annotations for controlling how serializers and parsers (and associated filters and properties) are inherited from the class.
      This replaces the previous addSerializers and addParsers annotations.
  • New RestServletJenaDefault servlet that includes serialization/parsing support for all Jena-based serializers and parsers.
  • New DefaultJenaProvider JAX-RS provider that includes serialization/parsing support for all Jena-based serializers and parsers.
  • Eliminated RestServletChild class.
    It's redundant with the introduction of inheritable annotations.
  • New methods on RestServlet:
    • RestServlet.createConfigFactory()
    • RestServlet.createSerializers()
    • RestServlet.createParsers()
    These augment the existing getBeanContext() / getSerializers() / getParsers() methods.
REST client API changes
  • New RestCall.setDateHeader(String,Object) method for setting ISO8601 datetime headers. (Apr 1, 2013)

Juno is a minor update. (Mar 27, 2013)

Juno is a moderate update.

The biggest change is the introduction of the RdfSerializer class that uses Jena to generate RDF/XML, RDF/XML-ABBREV, N-Tuple, N3, and Turtle output.

This code should be considered prototype-quality, and subject to change in the future.
There are plans of adding an equivalent RdfParser class in the future, so the serializer logic may need to be tweaked to allow POJOs to be reconstituted correctly in the parser.

The RdfXmlSerializer class should be considered deprecated for now.
However, I'm keeping it around, since it's considerably faster and uses far less memory than the Jena-based serializer since it serializes directly from POJOs to RDF/XML.
It may or may not be removed in the future depending on demand.

Other changes (Mar 25, 2013)

Juno is a minor update.

  • Charset now passed as a parameter to IOutputStreamSerializer.serialize() and IInputStreamParser.parse(). (Mar 25, 2013)

Juno is a minor update.

  • New @Properties REST method parameter annotation that can be used to get the runtime properties map through a parameter instead of through RestResponse. (Mar 24, 2013)

Juno is a moderate update.

  • Juno-Wink integration components that have been requested my many for a long time!
    Refer to for information.
  • New @Produces annotation in place of ISerializer.getMediaTypes() for specifying what media types a serializer produces.
    Available when subclassing from Serializer.
  • New @Consumes annotation in place of IParser.getMediaTypes() for specifying what media types a parser consumes.
    Available when subclassing from Parser. (Mar 23, 2013)

Juno is a major update.

The biggest change is that the RestSerializer, RestParser, RestSerializerGroup, and RestParserGroup classes have been eliminated entirely.
Instead, the existing Serializer, Parser, SerializerGroup, and ParserGroup classes of the core API have been augmented to replace them.

Adoptions will be required if you have previously used these classes.

Core API changes
REST server API changes
  • Eliminated and packages.
    • All existing REST serializers and parsers merged into the core API.
REST client API changes
  • Simplified RestClient API.
    • You can now only specify a single serializer or parser per client. This significantly simplifies the code.
    • Support for Encoders.
  • Eliminated RestCmdLine (since it's essentially redundant with CURL). (Mar 14, 2013)

Juno is a minor update.

Core API changes
  • New support for relative URIs.
    • URIs of the form "foo/bar" are interpreted as relative to the context root of the web application.
    • URIs of the form "/foo/bar" are interpreted as relative to the HTTP authority (e.g. "http://myhost:9080").
  • New SerializerContext.SERIALIZER_uriContext and SerializerContext.SERIALIZER_uriAuthority serializer properties for specifying values for relative URIs.
  • New @URI annotation that allows you to specify classes and bean properties as URLs that aren't or
  • New HtmlSerializerContext.HTML_uriAnchorText HTML serializer property for tailoring how anchor text is rendered.
  • Renamed BeanProperty#uri annotation to BeanProperty#beanUri to make it clear that this property represents the URI of the bean itself instead of an arbitrary property containing a URI.
  • Removed BeanProperty#id annotation.
REST server API changes
  • Improvements to RestServlet to automatically handle relative URIs in POJOs.
    • SerializerContext.SERIALIZER_uriContext property set by default to web app context root.
    • SerializerContext.SERIALIZER_uriAuthority property set by default to the request scheme+hostname+port.
  • Fixed bug involving Accept-Charset header in Chrome that prevented HTML output from rendering correctly in that browser.
    Accept-Charset handling should now be fully W3C compliant. (Mar 10, 2013)

Juno is a minor update.

Core API changes
  • Relaxed method naming conventions when using @BeanProperty annotation.
    Methods with zero parameters are interpreted as getters, and methods with one parameter are interpreted as setters.
    Eliminated the BeanProperty.method annotation, since it's now unnecessary.
REST server API changes
  • Significantly improved response error messages.
    Older messages were rather cryptic. Error conditions should be much easier to debug now.
  • New PlainTextRestSerializer class for serializing "plain/text" requests.
    Useful for debugging purposes.
  • Readers and InputStreams can now be passed in as @Content parameters if you need direct access to the HTTP body content without involving the parsers.
    Equivalent to previously calling RestRequest.getInputStream() and RestRequest.getReader().
  • Improved support for the ?debug parameter.
    Dumps better information to the log file, such as all header parameters. (Mar 8, 2013)

Juno is a moderate update.

REST server API changes
  • New UrlEncodingRestSerializer and UrlEncodingRestParser classes.
    Allows parsing form posts directly to POJOs.
  • Support for Accept and Content-Type "application/x-www-form-urlencoded" added by default on RestServletDefault.
  • New RestServlet.renderError(HttpServletRequest,HttpServletResponse,RestException) method to allow customized handling of response errors. (Mar 7, 2013)

Juno is a minor update.

Core API changes
  • New ObjectMap.findKeyIgnoreCase(String) method.
  • HtmlSerializer will now create 2-dimensional tables for collections of mixed beans/maps if all object have the same set of property names/keys.
REST server API changes
  • New RestServletProperties class that defines all the class-level properties that can be set on the servlet.
  • Properties can be set through annotation, or new RestServlet.setProperty(String,Object) method.
  • New "?noTrace" URL parameter to prevent stack traces from being logged (for JUnit testing of error conditions).
  • New RestServletProperties.REST_useStackTraceHashes property to prevent the same stack trace from being logged multiple times.
  • New RestServletProperties.REST_renderResponseStackTraces property for preventing stack traces in responses for security reasons.
  • New overridable RestServlet.onError(HttpServletRequest,HttpServletResponse,RestException,boolean) and RestServlet.onSuccess(RestRequest,RestResponse,long) methods for plugging in your own logging and peformance monitoring.
  • Eliminated RestServlet.getInitParams() method, since it's now redundant with RestServlet.getProperties().
  • Header parameters passed as URL parameters are now case-insensitive. (Feb 26, 2013)

Juno is a moderate update.

Core API changes
  • INI config file support:
    • A convenient API for reading, writing, and manipulating INI files.
    • Ability to convert INI files to batch and shell environment variables.
    • Command-line interface for updating INI files.
    • Support for encoded INI file values.
  • Support for fluent-style bean setters (setters that return the bean itself).
  • Ability to use @Bean annotation to override bean identification settings.
  • New ObjectMap.cast(Class) method to convert ObjectMaps directly to beans.
REST server API changes
Other notes
  • Smaller library size (460kB). (Jan 30, 2013)

Juno is a minor update.

  • New INI file support.
    • Makes reading, updating, and manipulating INI configuration files a snap.
    • Supports automatic conversion of data types in line with the functionality of the rest of the product.
    • Comments and layout of INI files are persisted during saves. (Jan 20, 2013)

Juno is a major update.

Core API updates
  • Combined previous 3 libraries into a single library.
  • New ParserListener class.
    Adds ability to find and process unknown bean properties during parsing.
  • Enhancements to XmlParser:
    • Coalescing support
    • Validations support
    • Support for replacing entity references
    • Resolver support
    • Event allocator support
    • Trim-whitespace support
  • Enhanced XML support:
    • New @Xml.format annotation.
      Controls how POJOs get serialized to XML.
      Also allows you to collapse collections and arrays.
    • New @Xml.namespaces annotation.
      Namespaces can be defined at package, class, method, or field levels.
    • New @Xml.nsUri annotation.
      Shortcut for specifying namespace URIs.
    • New @Xml.valAttr annotation.
      Serializes a bean property value as an attribute.
    • Ability to override XS and XSI namespaces on XML and RDF/XML serializers.
    • Ability to override RDF namespace on RDF/XML serializer.
    • New more-efficient namespace resolution.
  • New configurable property classes for everything are now structured better and easier to locate and identify through the following new classes:
  • Enhancements to BeanContext:
    • Ability to mark bean properties as hidden using @BeanProperty.hidden() so that they don't get serialized.
    • Simplified ClassType ClassMeta API.
      Combined 4 classes into a single class.
    • New @Bean.filter and @BeanProperty.filter annotations.
      Used for defining filters on bean classes and bean properties instead of just globally through BeanContext.addTransforms(Class[]).
    • New PropertyNamer API / @Bean.propertyNamer annotation.
      Used for customizing bean property names.
    • New @BeanProperty.beanUri and annotations.
      Used for associating beans with URLs and IDs.
      Used by XML serializer to add a url attribute on a bean element.
      Used by RDF/XML serializer to construct rdf:resource attributes.
    • New annotation. Used for limiting properties on child elements.
  • Automatic support for URL and URI objects.
    • Converted to hrefs in HTML.
    • Converted to url attributes in XML.
    • Converted to resource:about attributes in RDF/XML.
  • Improvements to Javadocs.
  • Improved PojoQuery support.
REST client updates
  • GZIP compression support.
  • Bug fixes.
REST server updates
  • Support for overriding bean context and serializer properties in a REST method call through new RestResponse.setProperty(String,Object) method.
    For example, allows you to control whitespace options on a per-request basis.
  • Several new annotations on REST servlets:
    • @RestResource.filters() - Associate post-formatting filters on a resource level.
    • @RestResource.guards - Associate resource-level guards.
    • @RestResource.messages - Associate a resource bundle with a REST servlet. Comes with several convenience methods for looking up messages for the client locale.
    • - Override default bean context, serializer, and parser properties though an annotation.
  • Several new annotations on REST methods:
    • @RestMethod.filters() - Associate post-formatting filters on a method level.
    • @RestMethod.guards - Associate method-level guards.
  • New annotations on REST method parameters with automatic conversion:
    • @Attr - A parameter or URL variable value as a parsed POJO.
    • @Param - A query parameter value as a parsed POJO.
    • @PathRemainder - The remainder after a URL pattern match as a String.
    • @Header - An HTTP header value as a parsed POJO.
    • @Content - The HTTP content as a parsed POJO.
    • @Method - The HTTP method name as a String.
  • HTTP response content POJOs can now simply be returned from methods instead of calling RestResponse.setOutput(Object). (Oct 30, 2012)

Juno is a minor update that fixes a small bug in (Oct 29, 2012)

Juno is a major update.

  • New @RestChild annotation for identifying child resources.
  • New traversable and filterable attributes added to @RestMethod annotation.
    Eliminates the need for PojoResource and FilteredRestResource classes.
  • Simplified client API. Easier to use when making multiple connections to the same server.
  • Support for pluggable authentication in the client API.
  • Support for authenticating against Jazz Team Servers.
  • Support for rendering package-level Javadocs in REST resources.
  • Support for parsing of header values into specific object types.
  • Changed default XML representation to not include JSON-type attributes. Produces cleaner XML.
  • New resourceUri attributed added to @Bean annotation to associate beans with resource URIs.
    • Used for automatically creating hyperlinks in HtmlSerializer.
    • Used for automatically creating uri attributes in XmlSerializer.
    • Used for automatically creating rdf:about attributes in RdfXmlSerializer. (Oct 7, 2012)

Juno is a minor update.

  • New @RestMethod annoation on RestServlet methods.
    Allows the usage of URL pattern matching and automatic conversion of URL variables to arguments passed to method handlers.
    See RestServlet for more information.
  • Enhancements to BeanContext.convertToType(Object,Class) to be able to convert Strings to classes with fromString(String)/valueOf(String) static methods or T(String) constructors. (Oct 3, 2012)

Juno is a minor update.

  • Support for parsing into read-only beans (i.e. beans with only getters, property values set through constructor args).
    To support this, the @BeanConstructor annotation has been added.
  • Merged separate settings classes back into their base classes (simplifies the API).
  • SerializerGroups and ParserGroups now share BeanContexts to reduce memory consumption of class type metadata. (Sept 28, 2012)

Juno is a minor update.

  • Improvements to Javadocs. Most of the information in the Juno Starters Guide wiki has been moved into the overview and package-level javadocs.
    Since the information is now written in HTML, you can now copy and paste the code examples directly from the Javadocs.
    The code examples are also syntax-highlighted using CSS.
  • Support for defining default XML namespaces on packages and classes for the XML and RDF serializers.
  • Restructured the packages along content type support (e.g. all JSON support moved to org.apache.juneau.json).
  • Automatic support for parsing maps with Enum keys, and parsing Enum strings.
    This was previously possible using filters, but now it's built-in for all the parsers.
  • Replaced the ObjectList.toXArray() methods with a new elements(Class<T> type) method that's more efficient and avoids creating an unnecessary array.
  • Support for parsing into beans with read-only properties.
    New @BeanConstructor annotation allows you to specify bean property values to be passed in through a constructor.
  • Separated the rest library into separate independent client and server libraries.
    Use one, use both, it's up to you. (Jun 14, 2012)

Juno is a moderate update.

  • New support for generating XML-Schema documents from POJO models.
  • New support for serializing to RDF/XML. (Jun 11, 2012)

Version 5.0 marks a major release milestone for the Juno/JJSON library. It is now available for download from iRAM under the name "Juno (previously JJSON)". The Juno Starters Guide has been updated to reflect new functionality in this release.

  • New name.
    Unfortunately, "JJSON" was already trademarked by another similar library. Therefore, it's been renamed "Juno" (after the Roman goddess and wife of Jupiter) which does not appear to have any similar trademark issues (crosses fingers). The name is also a play on the word "Uno", indicating that this is a single simple unifying interface of several kinds of technology.
  • Simplified APIs for working with beans.
    Significant improvements have been made to the parsers to make it easier to convert serialized POJOs back into their original forms.
  • Serializer/Parser classes now directly subclass from BeanContext.
    In previous releases, if you wanted to change the way beans were handled by the serializers and parsers, you had to construct a separate bean map factory and pass it to the serializer or parser. Now, you can call the bean map factory methods directly on the serializer or parser class.
  • Simplified Filter API for handling non-standard POJOs.
    The API for handling non-standard POJOs has been simplified by introducing the concept of a Transform class, which is associated with the BeanContext class (and thus the Serializer and Parser classes too) through the BeanContext.addTransforms(Class[]) method.
    Two new subclasses of Transform: This new API replaces the previous separate Cast and BeanFilter APIs which were considerably more complicated and puts them under a common API.
  • Elimination of _class attributes in parsable output.
    One of the complaints about the previous version of JJSON was that if you wanted to have the resulting JSON or XML be parsable back into beans, you had to enable the "addClassAttrs" property on the bean map factory class so that "_class" attributes could be added to the output.
    This requirement is virtually eliminated in v5. In many cases, the parsers are able to determine through reflection what the correct target type is based on the top-level class passed in on the parse method.
  • Performance improvements.
    Several significant performance improvements have been made in this release.
    • New Reader-based JSON parser.
      Previously, the JSON parser required that the entire JSON text be loaded into memory as a String before being parsed. The new JSON parser is Reader-based which significantly reduces memory consumption.
    • New StAX-based XML parser.
      The old XML parser was based on DOM. The new XML parser uses a StAX parser which significantly reduces memory consumption.
    • Caching of reflection data in the BeanMap API.
      The number of reflection calls have been significantly reduced in the BeanMap API code. Reflection is used to determine the class types of property values on beans. This information is now cached and persisted so that the reflection API calls to determine class types are only performed the first time a bean type is encountered.
    • Automatic support for GZIP compression/decompression in RestServlets.
      This is completely transparent to the developer. The output writer is negotiated by the framework to automatically handle compression and charset requests without the developer needing to know anything about it.
  • Cognos/XML support.
  • JSON-schema support.
  • New PojoIntrospector class.
  • Significant REST servlet API improvements.
    • Defining child resources is considerably simpler now. In addition to the standard doX() methods for handling the requests for the current resource, you can also define getX() methods for returning child resources which automatically become available under the child URL specified by the getter name.
    • Initialization of the child resources occurs automatically when the parent resource initialization occurs.
    • Other improvments have been made in the area of automatic negotiation of input and output type streams. For example, automatic support is provided for GZIP (Accept-Encoding: gzip) and charsets (e.g Accept-Charset: SJIS) on both incoming and outgoing data. It's all transparent from a developers perspective. The developer simply working with POJOs, and all details about content types, encoding, charsets, and so forth are handled by the framework.
    • Support for generating complex OPTIONS pages for resources.
  • Automatic support for SOAP XML output on "text/soap+xml" requests against RestServlet.
  • Support for XML namespaces.
  • Support for setting the XML root element name by either passing in a parameter on the serializer, or by specifying it via a @Bean annotation.
  • Support for loading beans directly from Readers and Strings.
  • Parsing support for POJOs of type Enum.
  • Significant improved support for various flavors of parameterized types, such as subclasses of parameterized types (e.g. MyBeanList extends LinkedList<MyBean>).
  • Improved ordering of bean properties (should now be ordered as they are defined in the class).
  • Various default filters provided:
    • byte[]<-->Base64 encoded strings
    • Date/Calendar<-->ISO8601/RFC822/Long
  • New HtmlParser and UrlEncodingParser classes.
  • HtmlSerializer now produces XHTML.
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