001// ***************************************************************************************************************************
002// * Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements.  See the NOTICE file *
003// * distributed with this work for additional information regarding copyright ownership.  The ASF licenses this file        *
004// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance            *
005// * with the License.  You may obtain a copy of the License at                                                              *
006// *                                                                                                                         *
007// *  http://www.apache.org/licenses/LICENSE-2.0                                                                             *
008// *                                                                                                                         *
009// * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an  *
010// * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the License for the        *
011// * specific language governing permissions and limitations under the License.                                              *
012// ***************************************************************************************************************************
013package org.apache.juneau.json.annotation;
014
015import static java.lang.annotation.ElementType.*;
016import static java.lang.annotation.RetentionPolicy.*;
017
018import java.lang.annotation.*;
019
020/**
021 * Annotation for specifying various JSON options for the JSON serializers and parsers.
022 *
023 * <p>
024 * Can be applied to Java types.
025 *
026 * <p>
027 * Can be used for the following:
028 * <ul class='spaced-list'>
029 *    <li>
030 *       Wrap bean instances inside wrapper object (e.g. <c>{'wrapperAttr':bean}</c>).
031 * </ul>
032 */
033@Documented
034@Target({TYPE,METHOD,FIELD})
035@Retention(RUNTIME)
036@Inherited
037public @interface Json {
038
039   /**
040    * Dynamically apply this annotation to the specified classes/methods/fields.
041    *
042    * <p>
043    * Used in conjunction with the {@link JsonConfig#applyJson()}.
044    * It is ignored when the annotation is applied directly to classes/methods/fields.
045    *
046    * <h5 class='section'>Valid patterns:</h5>
047    * <ul class='spaced-list'>
048    *  <li>Classes:
049    *       <ul>
050    *          <li>Fully qualified:
051    *             <ul>
052    *                <li><js>"com.foo.MyClass"</js>
053    *             </ul>
054    *          <li>Fully qualified inner class:
055    *             <ul>
056    *                <li><js>"com.foo.MyClass$Inner1$Inner2"</js>
057    *             </ul>
058    *          <li>Simple:
059    *             <ul>
060    *                <li><js>"MyClass"</js>
061    *             </ul>
062    *          <li>Simple inner:
063    *             <ul>
064    *                <li><js>"MyClass$Inner1$Inner2"</js>
065    *                <li><js>"Inner1$Inner2"</js>
066    *                <li><js>"Inner2"</js>
067    *             </ul>
068    *       </ul>
069    *    <li>Methods:
070    *       <ul>
071    *          <li>Fully qualified with args:
072    *             <ul>
073    *                <li><js>"com.foo.MyClass.myMethod(String,int)"</js>
074    *                <li><js>"com.foo.MyClass.myMethod(java.lang.String,int)"</js>
075    *                <li><js>"com.foo.MyClass.myMethod()"</js>
076    *             </ul>
077    *          <li>Fully qualified:
078    *             <ul>
079    *                <li><js>"com.foo.MyClass.myMethod"</js>
080    *             </ul>
081    *          <li>Simple with args:
082    *             <ul>
083    *                <li><js>"MyClass.myMethod(String,int)"</js>
084    *                <li><js>"MyClass.myMethod(java.lang.String,int)"</js>
085    *                <li><js>"MyClass.myMethod()"</js>
086    *             </ul>
087    *          <li>Simple:
088    *             <ul>
089    *                <li><js>"MyClass.myMethod"</js>
090    *             </ul>
091    *          <li>Simple inner class:
092    *             <ul>
093    *                <li><js>"MyClass$Inner1$Inner2.myMethod"</js>
094    *                <li><js>"Inner1$Inner2.myMethod"</js>
095    *                <li><js>"Inner2.myMethod"</js>
096    *             </ul>
097    *       </ul>
098    *    <li>Fields:
099    *       <ul>
100    *          <li>Fully qualified:
101    *             <ul>
102    *                <li><js>"com.foo.MyClass.myField"</js>
103    *             </ul>
104    *          <li>Simple:
105    *             <ul>
106    *                <li><js>"MyClass.myField"</js>
107    *             </ul>
108    *          <li>Simple inner class:
109    *             <ul>
110    *                <li><js>"MyClass$Inner1$Inner2.myField"</js>
111    *                <li><js>"Inner1$Inner2.myField"</js>
112    *                <li><js>"Inner2.myField"</js>
113    *             </ul>
114    *       </ul>
115    *    <li>A comma-delimited list of anything on this list.
116    * </ul>
117    *
118    * <ul class='seealso'>
119    *    <li class='link'>{@doc juneau-marshall.DynamicallyAppliedAnnotations}
120    * </ul>
121    */
122   String on() default "";
123
124   /**
125    * Wraps beans in a JSON object with the specified attribute name.
126    *
127    * <p>
128    * Applies only to {@link ElementType#TYPE}.
129    *
130    * <p>
131    * This annotation can be applied to beans as well as other objects serialized to other types (e.g. strings).
132    *
133    * <h5 class='figure'>Example:</h5>
134    * <p class='bcode w800'>
135    *    <ja>@Json</ja>(wrapperAttr=<js>"myWrapper"</js>)
136    *    <jk>public class</jk> MyBean {
137    *       <jk>public int</jk> f1 = 123;
138    *    }
139    * </p>
140    *
141    * <p>
142    * Without the <ja>@Json</ja> annotations, serializing this bean as JSON would have produced the following...
143    * <p class='bcode w800'>
144    *    {
145    *       f1: 123
146    *    }
147    * </p>
148    *
149    * <p>
150    * With the annotations, serializing this bean as JSON produces the following...
151    * <p class='bcode w800'>
152    *    {
153    *       myWrapper: {
154    *          f1: 123
155    *       }
156    *    }
157    * </p>
158    */
159   String wrapperAttr() default "";
160}