Jackson is "the Java JSON library" or "the best JSON parser for Java". Or simply as "JSON for Java".

Jackson Annotations Source Code files are provided in the source packge (jackson-annotations-2.14.0-sources.jar). You can download it at Jackson Maven Website.

You can also browse Jackson Annotations Source Code below:

⏎ com/fasterxml/jackson/annotation/JsonIdentityInfo.java

package com.fasterxml.jackson.annotation;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * Annotation used for indicating that values of annotated type
 * or property should be serializing so that instances either
 * contain additional object identifier (in addition actual object
 * properties), or as a reference that consists of an object id
 * that refers to a full serialization. In practice this is done
 * by serializing the first instance as full object and object
 * identity, and other references to the object as reference values.
 *<p>
 * There are two main approaches to generating object identifier:
 * either using a generator (either one of standard ones, or a custom
 * generator), or using a value of a property. The latter case is
 * indicated by using a placeholder generator marker
 * {@link ObjectIdGenerators.PropertyGenerator}; former by using explicit generator.
 * Object id has to be serialized as a property in case of POJOs;
 * object identity is currently NOT support for JSON Array types
 * (Java arrays or Lists) or Java Map types.
 *<p>
 * Finally, note that generator type of {@link ObjectIdGenerators.None}
 * indicates that no Object Id should be included or used: it is included
 * to allow suppressing Object Ids using mix-in annotations.
 * 
 * @since 2.0
 */
@Target({ElementType.ANNOTATION_TYPE, ElementType.TYPE,
    ElementType.FIELD, ElementType.METHOD, ElementType.PARAMETER})
@Retention(RetentionPolicy.RUNTIME)
@JacksonAnnotation
public @interface JsonIdentityInfo
{
    /**
     * Name of JSON property in which Object Id will reside: also,
     * if "from property" marker generator is used, identifies
     * property that will be accessed to get type id.
     * If a property is used, name must match its external
     * name (one defined by annotation, or derived from accessor
     * name as per Java Bean Introspection rules).
     *<p>
     * Default value is <code>@id</code>.
     */
    public String property() default "@id";

    /**
     * Generator to use for producing Object Identifier for objects:
     * either one of pre-defined generators from
     * {@link ObjectIdGenerator}, or a custom generator.
     * Defined as class to instantiate.
     *<p>
     * Note that special type
     * {@link ObjectIdGenerators.None}
     * can be used to disable inclusion of Object Ids.
     */
    public Class<? extends ObjectIdGenerator<?>> generator();

    /**
     * Resolver to use for producing POJO from Object Identifier.
     * <p>
     * Default value is {@link SimpleObjectIdResolver}
     * 
     * @since 2.4
     */
    public Class<? extends ObjectIdResolver> resolver() default SimpleObjectIdResolver.class;

    /**
     * Scope is used to define applicability of an Object Id: all ids
     * must be unique within their scope; where scope is defined
     * as combination of this value and generator type.
     * Comparison is simple equivalence, meaning that both type
     * generator type and scope class must be the same.
     *<p>
     * Scope is used for determining how many generators are needed;
     * more than one scope is typically only needed if external Object Ids
     * have overlapping value domains (i.e. are only unique within some
     * limited scope)
     */
    public Class<?> scope() default Object.class;
}

⏎ com/fasterxml/jackson/annotation/JsonIdentityInfo.java

Or download all of them as a single archive file:

File name: jackson-annotations-2.14.0-sources.jar
File size: 80402 bytes
Release date: 2022-11-05
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