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/util/LookupCache.java

package com.fasterxml.jackson.databind.util;

/**
 * An interface describing the required API for the Jackson-databind Type cache.
 *<p>
 * Note that while interface itself does not specify synchronization requirements for
 * implementations, specific use cases do. Typically implementations are
 * expected to be thread-safe, that is, to handle synchronization.
 *
 * @since 2.12 (for forwards-compatiblity with 3.0)
 */
public interface LookupCache <K,V>
{
    /**
     * @return Number of entries currently in cache: may be approximate, only
     *    to be used for diagnostics, metrics reporting
     */
    int size();

    /**
     * NOTE: key is of type Object only to retain binary backwards-compatibility
     *
     * @param key
     * @return value associated with key (can return null)
     */
    V get(Object key);

    V put(K key, V value);

    V putIfAbsent(K key, V value);

    /**
     * Method for removing all contents this cache has.
     */
    void clear();
}

⏎ com/fasterxml/jackson/databind/util/LookupCache.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