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/JsonSubTypes.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 with {@link JsonTypeInfo} to indicate subtypes of serializable
 * polymorphic types, and to associate logical names used within JSON content
 * (which is more portable than using physical Java class names).
 *<p>
 * Note that just annotating a property or base type with this annotation does
 * NOT enable polymorphic type handling: in addition, {@link JsonTypeInfo}
 * or equivalent (such as enabling of so-called "default typing") annotation
 * is needed, and only in such case is subtype information used.
 */
@Target({ElementType.ANNOTATION_TYPE, ElementType.TYPE, ElementType.FIELD,
    ElementType.METHOD, ElementType.PARAMETER})
@Retention(RetentionPolicy.RUNTIME)
@JacksonAnnotation
public @interface JsonSubTypes {
    /**
     * Subtypes of the annotated type (annotated class, or property value type
     * associated with the annotated method). These will be checked recursively
     * so that types can be defined by only including direct subtypes.
     */
    public Type[] value();

    /**
     * Subtypes of the annotated type may have logical type name and names properties.
     * When set to true, logical type name and names are going to be checked
     * for repeated values. Repeated values are considered a definition violation
     * during that check.
     *
     * @since 2.14
     */
    public boolean failOnRepeatedNames() default false;

    /**
     * Definition of a subtype, along with optional name(s). If no name is defined
     * (empty Strings are ignored), class of the type will be checked for {@link JsonTypeName}
     * annotation; and if that is also missing or empty, a default
     * name will be constructed by type id mechanism.
     * Default name is usually based on class name.
     */
    public @interface Type {
        /**
         * Class of the subtype
         */
        public Class<?> value();

        /**
         * Logical type name used as the type identifier for the class, if defined; empty
         * String means "not defined". Used unless {@link #names} is defined as non-empty.
         */
        public String name() default "";

        /**
         * (optional) Logical type names used as the type identifier for the class: used if
         * more than one type name should be associated with the same type.
         *
         * @since 2.12
         */
        public String[] names() default {};
    }
}

⏎ com/fasterxml/jackson/annotation/JsonSubTypes.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
Download 

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