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/module/SimpleKeyDeserializers.java

package com.fasterxml.jackson.databind.module;

import java.util.Collection;
import java.util.HashMap;
import java.util.Map;


import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.deser.KeyDeserializers;
import com.fasterxml.jackson.databind.type.ClassKey;

/**
 * Simple implementation {@link KeyDeserializers} which allows registration of
 * deserializers based on raw (type erased class).
 * It can work well for basic bean and scalar type deserializers, but is not
 * a good fit for handling generic types (like {@link Map}s and {@link Collection}s
 * or array types).
 *<p>
 * Unlike {@link SimpleSerializers}, this class does not currently support generic mappings;
 * all mappings must be to exact declared deserialization type.
 */
public class SimpleKeyDeserializers
    implements KeyDeserializers, java.io.Serializable // since 2.1
{
    private static final long serialVersionUID = 1L;

    protected HashMap<ClassKey,KeyDeserializer> _classMappings = null;

    /*
    /**********************************************************
    /* Life-cycle, construction and configuring
    /**********************************************************
     */
    
    public SimpleKeyDeserializers() { }

    public SimpleKeyDeserializers addDeserializer(Class<?> forClass, KeyDeserializer deser)
    {
        if (_classMappings == null) {
            _classMappings = new HashMap<ClassKey,KeyDeserializer>();
        }
        _classMappings.put(new ClassKey(forClass), deser);
        return this;
    }

    /*
    /**********************************************************
    /* Serializers implementation
    /**********************************************************
     */

    @Override
    public KeyDeserializer findKeyDeserializer(JavaType type,
            DeserializationConfig config, BeanDescription beanDesc)
    {
        if (_classMappings == null) {
            return null;
        }
        return _classMappings.get(new ClassKey(type.getRawClass()));
    }
}

⏎ com/fasterxml/jackson/databind/module/SimpleKeyDeserializers.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
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