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/node/BigIntegerNode.java

package com.fasterxml.jackson.databind.node;

import java.io.IOException;
import java.math.BigDecimal;
import java.math.BigInteger;

import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.databind.SerializerProvider;

/**
 * Numeric node that contains simple 64-bit integer values.
 */
@SuppressWarnings("serial")
public class BigIntegerNode
    extends NumericNode
{
    private final static BigInteger MIN_INTEGER = BigInteger.valueOf(Integer.MIN_VALUE);
    private final static BigInteger MAX_INTEGER = BigInteger.valueOf(Integer.MAX_VALUE);
    private final static BigInteger MIN_LONG = BigInteger.valueOf(Long.MIN_VALUE);
    private final static BigInteger MAX_LONG = BigInteger.valueOf(Long.MAX_VALUE);

    final protected BigInteger _value;

    /*
    /**********************************************************
    /* Construction
    /**********************************************************
     */

    public BigIntegerNode(BigInteger v) { _value = v; }

    public static BigIntegerNode valueOf(BigInteger v) { return new BigIntegerNode(v); }

    /* 
    /**********************************************************
    /* Overridden JsonNode methods
    /**********************************************************
     */

    @Override
    public JsonToken asToken() { return JsonToken.VALUE_NUMBER_INT; }

    @Override
    public JsonParser.NumberType numberType() { return JsonParser.NumberType.BIG_INTEGER; }

    @Override
    public boolean isIntegralNumber() { return true; }

    @Override
    public boolean isBigInteger() { return true; }

    @Override public boolean canConvertToInt() {
        return (_value.compareTo(MIN_INTEGER) >= 0) && (_value.compareTo(MAX_INTEGER) <= 0);
    }
    @Override public boolean canConvertToLong() {
        return (_value.compareTo(MIN_LONG) >= 0) && (_value.compareTo(MAX_LONG) <= 0);
    }
    
    @Override
    public Number numberValue() {
        return _value;
    }

    @Override
    public short shortValue() { return _value.shortValue(); }

    @Override
    public int intValue() { return _value.intValue(); }

    @Override
    public long longValue() { return _value.longValue(); }

    @Override
    public BigInteger bigIntegerValue() { return _value; }

    @Override
    public float floatValue() { return _value.floatValue(); }

    @Override
    public double doubleValue() { return _value.doubleValue(); }

    @Override
    public BigDecimal decimalValue() { return new BigDecimal(_value); }

    /* 
    /**********************************************************
    /* General type coercions
    /**********************************************************
     */
    
    @Override
    public String asText() {
        return _value.toString();
    }

    @Override
    public boolean asBoolean(boolean defaultValue) {
        return !BigInteger.ZERO.equals(_value);
    }
    
    @Override
    public final void serialize(JsonGenerator g, SerializerProvider provider)
        throws IOException
    {
        g.writeNumber(_value);
    }

    @Override
    public boolean equals(Object o)
    {
        if (o == this) return true;
        if (o == null) return false;
        if (!(o instanceof BigIntegerNode)) {
            return false;
        }
        return ((BigIntegerNode) o)._value.equals(_value);
    }

    @Override
    public int hashCode() {
        return _value.hashCode();
    }
}

⏎ com/fasterxml/jackson/databind/node/BigIntegerNode.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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