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

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

You can also browse Jackson Databind Source Code below:

⏎ com/fasterxml/jackson/databind/jsonschema/JsonSerializableSchema.java

package com.fasterxml.jackson.databind.jsonschema;

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

import com.fasterxml.jackson.annotation.JacksonAnnotation;

/**
 * Annotation that can be used to define JSON Schema definition for
 * the annotated class.
 *<p>
 * Note that annotation is often not needed: for example, regular
 * Jackson beans that Jackson can introspect can be used without
 * annotations, to produce JSON schema definition.
 * 
 * @author Ryan Heaton
 * @author Tatu Saloranta
 */
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@JacksonAnnotation
public @interface JsonSerializableSchema
{
    /**
     * Marker value used to indicate that property has "no value";
     * needed because annotations cannot have null as default
     * value.
     */
    public final static String NO_VALUE = "##irrelevant";

    /**
     * Property that can be used to indicate id of the type when
     * generating JSON Schema; empty String indicates that no id
     * is defined.
     */
    public String id() default "";
    
    /**
     * The schema type for this JsonSerializable instance.
     * Possible values: "string", "number", "boolean", "object", "array", "null", "any"
     *
     * @return The schema type for this JsonSerializable instance.
     */
    public String schemaType() default "any";

    /**
     * If the schema type is "object", JSON definition of properties of the object as
     * a String.
     *
     * @return The node representing the schema properties, or "##irrelevant" if irrelevant.
     * 
     * @deprecated (since 2.1) -- support will be dropped in future, since JSON-as-String is
     *   fundamentally bad way for customizing anything. No direct replacements offered.
     */
    @Deprecated
    public String schemaObjectPropertiesDefinition() default NO_VALUE;

    /**
     * If the schema type if "array", JSON definition of the schema for item types contained.
     *
     * @return The schema for the items in the array, or "##irrelevant" if irrelevant.
     * 
     * @deprecated (since 2.1) -- support will be dropped in future, since JSON-as-String is
     *   fundamentally bad way for customizing anything. No direct replacements offered.
     */
    @Deprecated
    public String schemaItemDefinition() default NO_VALUE;
}

⏎ com/fasterxml/jackson/databind/jsonschema/JsonSerializableSchema.java

Or download all of them as a single archive file:

File name: jackson-databind-2.14.0-sources.jar
File size: 1187952 bytes
Release date: 2022-11-05
Download 

⇒ Jackson Annotations Source Code

⇐ Download and Install Jackson Binary Package

⇑ Downloading and Reviewing jackson-*.jar

⇑⇑ Jackson - Java JSON library