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/std/DelegatingDeserializer.java

package com.fasterxml.jackson.databind.deser.std;

import java.io.IOException;
import java.util.Collection;

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.deser.*;
import com.fasterxml.jackson.databind.deser.impl.ObjectIdReader;
import com.fasterxml.jackson.databind.jsontype.TypeDeserializer;
import com.fasterxml.jackson.databind.type.LogicalType;
import com.fasterxml.jackson.databind.util.AccessPattern;

/**
 * Base class that simplifies implementations of {@link JsonDeserializer}s
 * that mostly delegate functionality to another deserializer implementation
 * (possibly forming a chaing of deserializers delegating functionality
 * in some cases)
 * 
 * @since 2.1
 */
public abstract class DelegatingDeserializer
    extends StdDeserializer<Object>
    implements ContextualDeserializer, ResolvableDeserializer
{
    private static final long serialVersionUID = 1L;

    protected final JsonDeserializer<?> _delegatee;
    
    /*
    /**********************************************************************
    /* Construction
    /**********************************************************************
     */

    public DelegatingDeserializer(JsonDeserializer<?> d)
    {
        super(d.handledType());
        _delegatee = d;
    }

    /*
    /**********************************************************************
    /* Abstract methods to implement
    /**********************************************************************
     */
    
    protected abstract JsonDeserializer<?> newDelegatingInstance(JsonDeserializer<?> newDelegatee);
    
    /*
    /**********************************************************************
    /* Overridden methods for contextualization, resolving
    /**********************************************************************
     */

    @Override
    public void resolve(DeserializationContext ctxt) throws JsonMappingException {
        if (_delegatee instanceof ResolvableDeserializer) {
            ((ResolvableDeserializer) _delegatee).resolve(ctxt);
        }
    }

    @Override
    public JsonDeserializer<?> createContextual(DeserializationContext ctxt,
            BeanProperty property)
        throws JsonMappingException
    {
        JavaType vt = ctxt.constructType(_delegatee.handledType());
        JsonDeserializer<?> del = ctxt.handleSecondaryContextualization(_delegatee,
                property, vt);
        if (del == _delegatee) {
            return this;
        }
        return newDelegatingInstance(del);
    }

    @Override
    public JsonDeserializer<?> replaceDelegatee(JsonDeserializer<?> delegatee)
    {
        if (delegatee == _delegatee) {
            return this;
        }
        return newDelegatingInstance(delegatee);
    }

    /*
    /**********************************************************************
    /* Overridden deserialization methods
    /**********************************************************************
     */

    @Override
    public Object deserialize(JsonParser p, DeserializationContext ctxt)
        throws IOException
    {
        return _delegatee.deserialize(p,  ctxt);
    }

    @SuppressWarnings("unchecked")
    @Override
    public Object deserialize(JsonParser p, DeserializationContext ctxt,
            Object intoValue)
        throws IOException
    {
        return ((JsonDeserializer<Object>)_delegatee).deserialize(p, ctxt, intoValue);
    }

    @Override
    public Object deserializeWithType(JsonParser p, DeserializationContext ctxt,
            TypeDeserializer typeDeserializer)
        throws IOException
    {
        return _delegatee.deserializeWithType(p, ctxt, typeDeserializer);
    }

    /*
    /**********************************************************************
    /* Overridden other methods
    /**********************************************************************
     */

    @Override
    public boolean isCachable() { return _delegatee.isCachable(); }

    @Override // since 2.9
    public Boolean supportsUpdate(DeserializationConfig config) {
        return _delegatee.supportsUpdate(config);
    }

    @Override
    public JsonDeserializer<?> getDelegatee() {
        return _delegatee;
    }

    @Override
    public SettableBeanProperty findBackReference(String logicalName) {
        // [databind#253]: Hope this works....
        return _delegatee.findBackReference(logicalName);
    }

    @Override
    public AccessPattern getNullAccessPattern() {
        return _delegatee.getNullAccessPattern();
    }

    @Override
    public Object getNullValue(DeserializationContext ctxt) throws JsonMappingException {
        return _delegatee.getNullValue(ctxt);
    }

    @Override
    public Object getEmptyValue(DeserializationContext ctxt) throws JsonMappingException {
        return _delegatee.getEmptyValue(ctxt);
    }

    @Override // since 2.12
    public LogicalType logicalType() {
        return _delegatee.logicalType();
    }

    @Override
    public Collection<Object> getKnownPropertyNames() { return _delegatee.getKnownPropertyNames(); }

    @Override
    public ObjectIdReader getObjectIdReader() { return _delegatee.getObjectIdReader(); }
}

⏎ com/fasterxml/jackson/databind/deser/std/DelegatingDeserializer.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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