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/deser/KeyDeserializers.java

package com.fasterxml.jackson.databind.deser;

import com.fasterxml.jackson.databind.*;

/**
 * Interface that defines API for simple extensions that can provide additional deserializers
 * for deserializer Map keys of various types, from JSON property names.
 * Access is by a single callback method; instance is to either return
 * a configured {@link KeyDeserializer} for specified type, or null to indicate that it
 * does not support handling of the type. In latter case, further calls can be made
 * for other providers; in former case returned key deserializer is used for handling of
 * key instances of specified type.
 */
public interface KeyDeserializers
{
    public KeyDeserializer findKeyDeserializer(JavaType type, DeserializationConfig config, BeanDescription beanDesc) throws JsonMappingException;
}

⏎ com/fasterxml/jackson/databind/deser/KeyDeserializers.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

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⇑⇑ Jackson - Java JSON library