001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.juneau.bean.jsonschema;
018
019import static org.apache.juneau.commons.utils.StringUtils.*;
020import static org.apache.juneau.commons.utils.ThrowableUtils.*;
021import static org.apache.juneau.commons.utils.Utils.*;
022
023import java.io.*;
024import java.net.*;
025import java.util.concurrent.*;
026
027import org.apache.juneau.*;
028import org.apache.juneau.json.*;
029
030/**
031 * A container for retrieving JSON {@link JsonSchema} objects by URI.
032 *
033 * <p>
034 * Subclasses must implement one of the following methods to load schemas from external sources:
035 * <ul class='spaced-list'>
036 *    <li>
037 *       {@link #getReader(URI)} - If schemas should be loaded from readers and automatically parsed.
038 *    <li>
039 *       {@link #load(URI)} - If you want control over construction of {@link JsonSchema} objects.
040 * </ul>
041 *
042 * @serial exclude
043 */
044public abstract class JsonSchemaMap extends ConcurrentHashMap<URI,JsonSchema> {
045
046   private static final long serialVersionUID = 1L;
047
048   /**
049    * Convenience method for pre-populating this map with the specified schemas.
050    *
051    * <p>
052    * The schemas passed in through this method MUST have their ID properties set.
053    *
054    * @param schemas The set of schemas to add to this map.
055    * @return This object.
056    * @throws RuntimeException If one or more schema objects did not have their ID property set.
057    */
058   @SuppressWarnings("deprecation")
059   public JsonSchemaMap add(JsonSchema...schemas) {
060      for (var schema : schemas) {
061         if (schema.getId() == null)
062            throw illegalArg("Schema with no ID passed to JsonSchemaMap.add(Schema...)");
063         put(schema.getId(), schema);
064         schema.setSchemaMap(this);
065      }
066      return this;
067   }
068
069   /**
070    * Return the {@link JsonSchema} object at the specified URI.
071    *
072    * <p>
073    * If this schema object has not been loaded yet, calls {@link #load(URI)}.
074    *
075    * <p>
076    * The value can be of any of the following types: {@link URI}, {@link URL}, {@link String}.
077    * Strings must be valid URIs.
078    *
079    * <p>
080    * URIs defined by {@link UriResolver} can be used for values.
081    *
082    * @param uri The URI of the schema to retrieve.
083    * @return The JsonSchema, or <jk>null</jk> if schema was not located and could not be loaded.
084    */
085   @Override /* Overridden from Map */
086   public JsonSchema get(Object uri) {
087      var u = toUri(uri);
088      var s = super.get(u);
089      if (nn(s))
090         return s;
091      synchronized (this) {
092         s = load(u);
093         if (nn(s)) {
094            // Note:  Can't use add(Schema...) since the ID property may not be set.
095            s.setSchemaMap(this);
096            put(u, s);
097         }
098         return s;
099      }
100   }
101
102   /**
103    * Subclasses must implement either this method or {@link #load(URI)} to load the schema with the specified URI.
104    *
105    * <p>
106    * It's up to the implementer to decide where these come from.
107    *
108    * <p>
109    * The default implementation returns <jk>null</jk>.
110    *
111    * @param uri The URI to connect to and retrieve the contents.
112    * @return The reader from reading the specified URI.
113    */
114   public Reader getReader(URI uri) {
115      return null;
116   }
117
118   /**
119    * Subclasses must implement either this method or {@link #getReader(URI)} to load the schema with the specified URI.
120    *
121    * <p>
122    * It's up to the implementer to decide where these come from.
123    *
124    * <p>
125    * The default implementation calls {@link #getReader(URI)} and parses the schema document.
126    * If {@link #getReader(URI)} returns <jk>null</jk>, this method returns <jk>null</jk> indicating this is an
127    * unreachable document.
128    *
129    * @param uri The URI to load the schema from.
130    * @return The parsed schema.
131    */
132   public JsonSchema load(URI uri) {
133      try (var r = getReader(uri)) {
134         if (r == null)
135            return null;
136         return JsonParser.DEFAULT.parse(r, JsonSchema.class);
137      } catch (Exception e) {
138         throw toRex(e);
139      }
140   }
141}