Package org.apache.juneau.commons.reflect

Class PackageInfo

java.lang.Object

org.apache.juneau.commons.reflect.PackageInfo

All Implemented Interfaces:

Annotatable

public class PackageInfo
extends Object
implements Annotatable

Lightweight wrapper around a Package object providing convenient access to package metadata and annotations.

This class provides a cached wrapper around Java Package objects, extending the standard API with convenient methods for accessing package annotations and metadata. Instances are cached and reused for efficiency.

Features:

• Cached instances - package info objects are cached and reused
• Annotation support - get annotations declared on the package
• Convenient access - easy access to package name and metadata
• Thread-safe - instances are immutable and safe for concurrent access

Use Cases:

• Accessing package-level annotations
• Working with package metadata
• Building frameworks that need to analyze package information

Usage:

// Get PackageInfo from a class PackageInfo pi = PackageInfo.of(MyClass.class); // Get package name String name = pi.getName(); // Get annotations List<AnnotationInfo<MyAnnotation>> annotations = pi.getAnnotations(MyAnnotation.class).toList();

See Also:

• ClassInfo - Class introspection
• Reflection Package

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	PackageInfo(Package inner)	Constructor.

Method Summary

Modifier and Type	Method	Description
boolean	equals(Object obj)	Returns true if the specified object is equal to this package.
AnnotatableType	getAnnotatableType()	Returns the type of this annotatable object.
List<AnnotationInfo<Annotation>>	getAnnotations()	Returns all annotations on this package, wrapped in AnnotationInfo objects.
<A extends Annotation> Stream<AnnotationInfo<A>>	getAnnotations(Class<A> type)	Returns this package's annotations of the specified type (including repeated annotations), wrapped in AnnotationInfo.
String	getImplementationTitle()	Returns the title of this package's implementation.
String	getImplementationVendor()	Returns the name of the organization that provided this package's implementation.
String	getImplementationVersion()	Returns the version of this package's implementation.
String	getLabel()	Returns a human-readable label for this annotatable element.
String	getName()	Returns the name of this package.
String	getSpecificationTitle()	Returns the title of the specification that this package implements.
String	getSpecificationVendor()	Returns the name of the organization that maintains the specification implemented by this package.
String	getSpecificationVersion()	Returns the version number of the specification that this package implements.
int	hashCode()	Returns the hash code of this package.
Package	inner()	Returns the wrapped Package object.
boolean	isCompatibleWith(String desired)	Compares this package's specification version with a desired version.
boolean	isSealed()	Returns true if this package is sealed.
boolean	isSealed(URL url)	Returns true if this package is sealed with respect to the specified code source URL.
static PackageInfo	of(Class<?> childClass)	Returns a package info wrapper around the package of the specified class.
static PackageInfo	of(Package inner)	Returns a package info wrapper around the specified package object.
static PackageInfo	of(ClassInfo childClass)	Returns a package info wrapper around the package of the specified class info.
String	toString()	Returns the string representation of this package.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Details

PackageInfo

protected PackageInfo(Package inner)

Constructor.

Parameters:

inner - The package object.

Method Details

of

public static PackageInfo of(Class<?> childClass)

Returns a package info wrapper around the package of the specified class.

Parameters:

childClass - The class whose package to retrieve.

Returns:

A package info wrapper.

of

public static PackageInfo of(ClassInfo childClass)

Returns a package info wrapper around the package of the specified class info.

Parameters:

childClass - The class info whose package to retrieve.

Returns:

A package info wrapper.

of

public static PackageInfo of(Package inner)

Returns a package info wrapper around the specified package object.

Parameters:

inner - The package object.

Returns:

A package info wrapper.

equals

public boolean equals(Object obj)

Returns true if the specified object is equal to this package.

Two packages are equal if they have the same name.

Overrides:

equals in class Object

Parameters:

obj - The object to compare to.

Returns:

true if the specified object is equal to this package.

getAnnotatableType

public AnnotatableType getAnnotatableType()

Description copied from interface: Annotatable

Returns the type of this annotatable object.

Specified by:

getAnnotatableType in interface Annotatable

Returns:

The type of annotatable object this represents.

getAnnotations

public List<AnnotationInfo<Annotation>> getAnnotations()

Returns all annotations on this package, wrapped in AnnotationInfo objects.

Cached and unmodifiable. Repeated annotations (from @Repeatable containers) have been automatically unwrapped and are present as individual instances in the list.

Returns:

All annotations present on this package, or an empty list if there are none.

getAnnotations

public <A extends Annotation>
Stream<AnnotationInfo<A>> getAnnotations(Class<A> type)

Returns this package's annotations of the specified type (including repeated annotations), wrapped in AnnotationInfo.

Filters the cached annotations list by type.

Type Parameters:

A - The annotation type.

Parameters:

type - The annotation type.

Returns:

A stream of annotation infos of the specified type, never null.

getImplementationTitle

public String getImplementationTitle()

Returns the title of this package's implementation.

Same as calling Package.getImplementationTitle().

Returns:

The implementation title, or null if it is not known.

See Also:

• Package.getImplementationTitle()

getImplementationVendor

public String getImplementationVendor()

Returns the name of the organization that provided this package's implementation.

Same as calling Package.getImplementationVendor().

Returns:

The implementation vendor, or null if it is not known.

See Also:

• Package.getImplementationVendor()

getImplementationVersion

public String getImplementationVersion()

Returns the version of this package's implementation.

Same as calling Package.getImplementationVersion().

Returns:

The implementation version, or null if it is not known.

See Also:

• Package.getImplementationVersion()

getLabel

public String getLabel()

Description copied from interface: Annotatable

Returns a human-readable label for this annotatable element.

The label format depends on the type of annotatable:

• CLASS_TYPE - Simple class name (e.g., "MyClass")
• METHOD_TYPE - Class and method with parameter types (e.g., "MyClass.myMethod(String,int)")
• FIELD_TYPE - Class and field name (e.g., "MyClass.myField")
• CONSTRUCTOR_TYPE - Class and constructor with parameter types (e.g., "MyClass.MyClass(String)")
• PARAMETER_TYPE - Class, method/constructor, and parameter index (e.g., "MyClass.myMethod[0]")
• PACKAGE_TYPE - Package name (e.g., "com.example.package")

Specified by:

getLabel in interface Annotatable

Returns:

The human-readable label for this annotatable element.

getName

public String getName()

Returns the name of this package.

Same as calling Package.getName().

Example:

PackageInfo pi = PackageInfo.of(String.class); String name = pi.getName(); // "java.lang"

Returns:

The fully-qualified name of this package.

See Also:

• Package.getName()

getSpecificationTitle

public String getSpecificationTitle()

Returns the title of the specification that this package implements.

Same as calling Package.getSpecificationTitle().

Returns:

The specification title, or null if it is not known.

See Also:

• Package.getSpecificationTitle()

getSpecificationVendor

public String getSpecificationVendor()

Returns the name of the organization that maintains the specification implemented by this package.

Same as calling Package.getSpecificationVendor().

Returns:

The specification vendor, or null if it is not known.

See Also:

• Package.getSpecificationVendor()

getSpecificationVersion

public String getSpecificationVersion()

Returns the version number of the specification that this package implements.

Same as calling Package.getSpecificationVersion().

This version string must be a sequence of nonnegative decimal integers separated by periods and may have leading zeros.

Returns:

The specification version, or null if it is not known.

See Also:

• Package.getSpecificationVersion()

hashCode

public int hashCode()

Returns the hash code of this package.

Same as calling Package.hashCode().

Overrides:

hashCode in class Object

Returns:

The hash code of this package.

inner

public Package inner()

Returns the wrapped Package object.

Returns:

The wrapped Package object.

isCompatibleWith

public boolean isCompatibleWith(String desired)
                         throws NumberFormatException

Compares this package's specification version with a desired version.

Same as calling Package.isCompatibleWith(String).

The version strings are compared by comparing each decimal integer in the version string.

Parameters:

desired - The desired version.

Returns:

true if this package's specification version is compatible with the desired version.

Throws:

NumberFormatException - If the desired or current version is not in the correct format.

See Also:

• Package.isCompatibleWith(String)

isSealed

public boolean isSealed()

Returns true if this package is sealed.

Same as calling Package.isSealed().

Returns:

true if this package is sealed.

See Also:

• Package.isSealed()

isSealed

public boolean isSealed(URL url)

Returns true if this package is sealed with respect to the specified code source URL.

Same as calling Package.isSealed(URL).

Parameters:

url - The code source URL.

Returns:

true if this package is sealed with respect to the specified URL.

See Also:

• Package.isSealed(URL)

toString

public String toString()

Returns the string representation of this package.

Same as calling Package.toString().

Example:

PackageInfo pi = PackageInfo.of(String.class); String s = pi.toString(); // "package java.lang"

Overrides:

toString in class Object

Returns:

The string representation of this package.

See Also:

• Package.toString()