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/impl/UnsupportedTypeDeserializer.java

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

import java.io.IOException;

import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.core.JsonToken;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.deser.std.StdDeserializer;

/**
 * Special bogus "serializer" that will throw
 * {@link com.fasterxml.jackson.databind.exc.MismatchedInputException}
 * if an attempt is made to deserialize a value.
 * This is used for "known unknown" types: types that we can recognize
 * but can not support easily (or support known to be added via extension
 * module).
 *<p>
 * NOTE: starting with 2.13, does allow deserialization from
 * {@code JsonToken.VALUE_EMBEDDED_OBJECT} if type matches (or is {@code null}).
 *
 * @since 2.12
 */
public class UnsupportedTypeDeserializer extends StdDeserializer<Object>
{
    private static final long serialVersionUID = 1L;

    protected final JavaType _type;

    protected final String _message;

    public UnsupportedTypeDeserializer(JavaType t, String m) {
        super(t);
        _type = t;
        _message = m;
    }
    
    @Override
    public Object deserialize(JsonParser p, DeserializationContext ctxt) throws IOException
    {
        // 26-May-2021, tatu: For [databind#3091], do allow reads from embedded values
        if (p.currentToken() == JsonToken.VALUE_EMBEDDED_OBJECT) {
            Object value = p.getEmbeddedObject();
            if ((value == null) || _type.getRawClass().isAssignableFrom(value.getClass())) {
                return value;
            }
        }
        ctxt.reportBadDefinition(_type, _message);
        return null;
    }
}

⏎ com/fasterxml/jackson/databind/deser/impl/UnsupportedTypeDeserializer.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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