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/IntNode.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.core.io.NumberOutput;
import com.fasterxml.jackson.databind.SerializerProvider;


/**
 * Numeric node that contains simple 32-bit integer values.
 */
@SuppressWarnings("serial")
public class IntNode
    extends NumericNode
{
    // // // Let's cache small set of common value

    final static int MIN_CANONICAL = -1;
    final static int MAX_CANONICAL = 10;

    private final static IntNode[] CANONICALS;
    static {
        int count = MAX_CANONICAL - MIN_CANONICAL + 1;
        CANONICALS = new IntNode[count];
        for (int i = 0; i < count; ++i) {
            CANONICALS[i] = new IntNode(MIN_CANONICAL + i);
        }
    }

    /**
     * Integer value this node contains
     */
    protected final int _value;

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

    public IntNode(int v) { _value = v; }

    public static IntNode valueOf(int i) {
        if (i > MAX_CANONICAL || i < MIN_CANONICAL) return new IntNode(i);
        return CANONICALS[i - MIN_CANONICAL];
    }

    /* 
    /**********************************************************
    /* BaseJsonNode extended API
    /**********************************************************
     */

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

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

    /* 
    /**********************************************************
    /* Overrridden JsonNode methods
    /**********************************************************
     */

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

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

    @Override public boolean canConvertToInt() { return true; }
    @Override public boolean canConvertToLong() { return true; }
    
    @Override
    public Number numberValue() {
        return Integer.valueOf(_value);
    }

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

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

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

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

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

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

    @Override
    public String asText() {
        return NumberOutput.toString(_value);
    }

    @Override
    public boolean asBoolean(boolean defaultValue) {
        return _value != 0;
    }
    
    @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 IntNode) {
            return ((IntNode) o)._value == _value;
        }
        return false;
    }

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

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