gson/com/google/gson/annotations/SerializedName.java

   1 /*
   2  * Copyright (C) 2008 Google Inc.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 package com.google.gson.annotations;
  18
  19 import java.lang.annotation.ElementType;
  20 import java.lang.annotation.Retention;
  21 import java.lang.annotation.RetentionPolicy;
  22 import java.lang.annotation.Target;
  23
  24 /**
  25  * An annotation that indicates this member should be serialized to JSON with
  26  * the provided name value as its field name.
  27  *
  28  * <p>This annotation will override any {@link com.google.gson.FieldNamingPolicy}, including
  29  * the default field naming policy, that may have been set on the {@link com.google.gson.Gson}
  30  * instance.  A different naming policy can set using the {@code GsonBuilder} class.  See
  31  * {@link com.google.gson.GsonBuilder#setFieldNamingPolicy(com.google.gson.FieldNamingPolicy)}
  32  * for more information.</p>
  33  *
  34  * <p>Here is an example of how this annotation is meant to be used:</p>
  35  * <pre>
  36  * public class SomeClassWithFields {
  37  *   &#64SerializedName("name") private final String someField;
  38  *   private final String someOtherField;
  39  *
  40  *   public SomeClassWithFields(String a, String b) {
  41  *     this.someField = a;
  42  *     this.someOtherField = b;
  43  *   }
  44  * }
  45  * </pre>
  46  *
  47  * <p>The following shows the output that is generated when serializing an instance of the
  48  * above example class:</p>
  49  * <pre>
  50  * SomeClassWithFields objectToSerialize = new SomeClassWithFields("a", "b");
  51  * Gson gson = new Gson();
  52  * String jsonRepresentation = gson.toJson(objectToSerialize);
  53  * System.out.println(jsonRepresentation);
  54  *
  55  * ===== OUTPUT =====
  56  * {"name":"a","someOtherField":"b"}
  57  * </pre>
  58  *
  59  * <p>NOTE: The value you specify in this annotation must be a valid JSON field name.</p>
  60  *
  61  * @see com.google.gson.FieldNamingPolicy
  62  *
  63  * @author Inderjeet Singh
  64  * @author Joel Leitch
  65  */
  66 @Retention(RetentionPolicy.RUNTIME)
  67 @Target(ElementType.FIELD)
  68 public @interface SerializedName {
  69
  70   /**
  71    * @return the desired name of the field when it is serialized
  72    */
  73   String value();
  74 }