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/TextNode.java

package com.fasterxml.jackson.databind.node;

import java.io.IOException;

import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.core.io.CharTypes;
import com.fasterxml.jackson.core.io.NumberInput;
import com.fasterxml.jackson.core.util.ByteArrayBuilder;

import com.fasterxml.jackson.databind.SerializerProvider;
import com.fasterxml.jackson.databind.exc.InvalidFormatException;

/**
 * Value node that contains a text value.
 */
public class TextNode
    extends ValueNode
{
    private static final long serialVersionUID = 2L;

    final static TextNode EMPTY_STRING_NODE = new TextNode("");

    protected final String _value;

    public TextNode(String v) { _value = v; }

    /**
     * Factory method that should be used to construct instances.
     * For some common cases, can reuse canonical instances: currently
     * this is the case for empty Strings, in future possible for
     * others as well. If null is passed, will return null.
     *
     * @return Resulting {@link TextNode} object, if <b>v</b>
     *   is NOT null; null if it is.
     */
    public static TextNode valueOf(String v)
    {
        if (v == null) {
            return null;
        }
        if (v.isEmpty()) {
            return EMPTY_STRING_NODE;
        }
        return new TextNode(v);
    }

    @Override
    public JsonNodeType getNodeType() {
        return JsonNodeType.STRING;
    }

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

    @Override
    public String textValue() {
        return _value;
    }

    /**
     * Method for accessing textual contents assuming they were
     * base64 encoded; if so, they are decoded and resulting binary
     * data is returned.
     */
    @SuppressWarnings("resource")
    public byte[] getBinaryValue(Base64Variant b64variant) throws IOException
    {
        final String str = _value.trim();
        // 04-Sep-2020, tatu: Let's limit the size of the initial block to 64k,
        //    no point in trying to exactly match the size beyond certain point
        // (plus it could even lead to unnecessarily high retention with block
        // recycling)
        final int initBlockSize = 4 + ((str.length() >> 2) * 3);
        ByteArrayBuilder builder = new ByteArrayBuilder(Math.max(16,
                Math.min(0x10000, initBlockSize)));
        try {
            b64variant.decode(str, builder);
        } catch (IllegalArgumentException e) {
            throw InvalidFormatException.from(null,
                    String.format(
"Cannot access contents of TextNode as binary due to broken Base64 encoding: %s",
e.getMessage()),
                    str, byte[].class);
        }
        return builder.toByteArray();
    }

    @Override
    public byte[] binaryValue() throws IOException {
        return getBinaryValue(Base64Variants.getDefaultVariant());
    }

    /* 
    /**********************************************************
    /* General type coercions
    /**********************************************************
     */

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

    @Override
    public String asText(String defaultValue) {
        return (_value == null) ? defaultValue : _value;
    }
    
    // note: neither fast nor elegant, but these work for now:

    @Override
    public boolean asBoolean(boolean defaultValue) {
        if (_value != null) {
            String v = _value.trim();
            if ("true".equals(v)) {
                return true;
            }
            if ("false".equals(v)) {
                return false;
            }
        }
        return defaultValue;
    }
    
    @Override
    public int asInt(int defaultValue) {
        return NumberInput.parseAsInt(_value, defaultValue);
    }

    @Override
    public long asLong(long defaultValue) {
        return NumberInput.parseAsLong(_value, defaultValue);
    }
    
    @Override
    public double asDouble(double defaultValue) {
        return NumberInput.parseAsDouble(_value, defaultValue);
    }
    
    /* 
    /**********************************************************
    /* Serialization
    /**********************************************************
     */
    
    @Override
    public final void serialize(JsonGenerator g, SerializerProvider provider) throws IOException
    {
        if (_value == null) {
            g.writeNull();
        } else {
            g.writeString(_value);
        }
    }

    /*
    /**********************************************************
    /* Overridden standard methods
    /**********************************************************
     */
    
    @Override
    public boolean equals(Object o)
    {
        if (o == this) return true;
        if (o == null) return false;
        if (o instanceof TextNode) {
            return ((TextNode) o)._value.equals(_value);
        }
        return false;
    }
    
    @Override
    public int hashCode() { return _value.hashCode(); }

    @Deprecated // since 2.10
    protected static void appendQuoted(StringBuilder sb, String content)
    {
        sb.append('"');
        CharTypes.appendQuoted(sb, content);
        sb.append('"');
    }
}

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