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/jsontype/impl/AsWrapperTypeSerializer.java

package com.fasterxml.jackson.databind.jsontype.impl;

import java.io.IOException;

import com.fasterxml.jackson.annotation.JsonTypeInfo.As;
import com.fasterxml.jackson.core.*;

import com.fasterxml.jackson.databind.BeanProperty;
import com.fasterxml.jackson.databind.jsontype.TypeIdResolver;
import com.fasterxml.jackson.databind.util.ClassUtil;

/**
 * Type wrapper that tries to use an extra JSON Object, with a single
 * entry that has type name as key, to serialize type information.
 * If this is not possible (value is serialize as array or primitive),
 * will use {@link As#WRAPPER_ARRAY} mechanism as fallback: that is,
 * just use a wrapping array with type information as the first element
 * and value as second.
 */
public class AsWrapperTypeSerializer extends TypeSerializerBase
{
    public AsWrapperTypeSerializer(TypeIdResolver idRes, BeanProperty property) {
        super(idRes, property);
    }

    @Override
    public AsWrapperTypeSerializer forProperty(BeanProperty prop) {
        return (_property == prop) ? this : new AsWrapperTypeSerializer(_idResolver, prop);
    }
    
    @Override
    public As getTypeInclusion() { return As.WRAPPER_OBJECT; }

    /*
    /**********************************************************
    /* Internal helper methods
    /**********************************************************
     */
    
    /**
     * Helper method used to ensure that intended type id is output as something that is valid:
     * currently only used to ensure that `null` output is converted to an empty String.
     *
     * @since 2.6
     */
    protected String _validTypeId(String typeId) {
        return ClassUtil.nonNullString(typeId);
    }

    // @since 2.9
    protected final void _writeTypeId(JsonGenerator g, String typeId) throws IOException
    {
        if (typeId != null) {
            g.writeTypeId(typeId);
        }
    }
}

⏎ com/fasterxml/jackson/databind/jsontype/impl/AsWrapperTypeSerializer.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 

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