Jackson is "the Java JSON library" or "the best JSON parser for Java". Or simply as "JSON for Java".

Jackson Core Source Code files are provided in the source packge (jackson-core-2.14.0-sources.jar). You can download it at Jackson Maven Website.

You can also browse Jackson Core Source Code below:

⏎ com/fasterxml/jackson/core/SerializableString.java

/* Jackson JSON-processor.
 *
 * Copyright (c) 2007- Tatu Saloranta, tatu.saloranta@iki.fi
 */

package com.fasterxml.jackson.core;

import java.io.IOException;
import java.io.OutputStream;
import java.nio.ByteBuffer;

/**
 * Interface that defines how Jackson package can interact with efficient
 * pre-serialized or lazily-serialized and reused String representations.
 * Typically implementations store possible serialized version(s) so that
 * serialization of String can be done more efficiently, especially when
 * used multiple times.
 *<p>
 * Note that "quoted" in methods means quoting of 'special' characters using
 * JSON backlash notation (and not use of actual double quotes).
 * 
 * @see com.fasterxml.jackson.core.io.SerializedString
 */
public interface SerializableString
{
    /**
     * Returns unquoted String that this object represents (and offers
     * serialized forms for)
     *
     * @return Unquoted String
     */
    String getValue();
    
    /**
     * Returns length of the (unquoted) String as characters.
     * Functionally equivalent to:
     *<pre>
     *   getValue().length();
     *</pre>
     *
     * @return Length of the String in characters
     */
    int charLength();

    /*
    /**********************************************************
    /* Accessors for byte sequences
    /**********************************************************
     */
    
    /**
     * Returns JSON quoted form of the String, as character array.
     * Result can be embedded as-is in textual JSON as property name or JSON String.
     *
     * @return JSON quoted form of the String as {@code char[]}
     */
    char[] asQuotedChars();

    /**
     * Returns UTF-8 encoded version of unquoted String.
     * Functionally equivalent to (but more efficient than):
     *<pre>
     * getValue().getBytes("UTF-8");
     *</pre>
     *
     * @return UTF-8 encoded version of String, without any escaping
     */
    byte[] asUnquotedUTF8();

    /**
     * Returns UTF-8 encoded version of JSON-quoted String.
     * Functionally equivalent to (but more efficient than):
     *<pre>
     * new String(asQuotedChars()).getBytes("UTF-8");
     *</pre>
     *
     * @return UTF-8 encoded version of JSON-escaped String
     */
    byte[] asQuotedUTF8();

    /*
    /**********************************************************
    /* Helper methods for appending byte/char sequences
    /**********************************************************
     */

    /**
     * Method that will append quoted UTF-8 bytes of this String into given
     * buffer, if there is enough room; if not, returns -1.
     * Functionally equivalent to:
     *<pre>
     *  byte[] bytes = str.asQuotedUTF8();
     *  System.arraycopy(bytes, 0, buffer, offset, bytes.length);
     *  return bytes.length;
     *</pre>
     *
     * @param buffer Buffer to append JSON-escaped String into
     * @param offset Offset in {@code buffer} to append String at
     *
     * @return Number of bytes appended, if successful, otherwise -1
     */
    int appendQuotedUTF8(byte[] buffer, int offset);

    /**
     * Method that will append quoted characters of this String into given
     * buffer. Functionally equivalent to:
     *<pre>
     *  char[] ch = str.asQuotedChars();
     *  System.arraycopy(ch, 0, buffer, offset, ch.length);
     *  return ch.length;
     *</pre>
     *
     * @param buffer Buffer to append JSON-escaped String into
     * @param offset Offset in {@code buffer} to append String at
     * 
     * @return Number of characters appended, if successful, otherwise -1
     */
    int appendQuoted(char[] buffer, int offset);
    
    /**
     * Method that will append unquoted ('raw') UTF-8 bytes of this String into given
     * buffer. Functionally equivalent to:
     *<pre>
     *  byte[] bytes = str.asUnquotedUTF8();
     *  System.arraycopy(bytes, 0, buffer, offset, bytes.length);
     *  return bytes.length;
     *</pre>
     *
     * @param buffer Buffer to append literal (unescaped) String into
     * @param offset Offset in {@code buffer} to append String at
     * 
     * @return Number of bytes appended, if successful, otherwise -1
     */
    int appendUnquotedUTF8(byte[] buffer, int offset);

    /**
     * Method that will append unquoted characters of this String into given
     * buffer. Functionally equivalent to:
     *<pre>
     *  char[] ch = str.getValue().toCharArray();
     *  System.arraycopy(bytes, 0, buffer, offset, ch.length);
     *  return ch.length;
     *</pre>
     *
     * @param buffer Buffer to append literal (unescaped) String into
     * @param offset Offset in {@code buffer} to append String at
     * 
     * @return Number of characters appended, if successful, otherwise -1
     */
    int appendUnquoted(char[] buffer, int offset);

    /*
    /**********************************************************
    /* Helper methods for writing out byte sequences
    /**********************************************************
     */

    /**
     * Method for writing JSON-escaped UTF-8 encoded String value using given
     * {@link java.io.OutputStream}.
     *
     * @param out {@link java.io.OutputStream} to write String into
     *
     * @return Number of bytes written
     *
     * @throws IOException if underlying stream write fails
     */
    int writeQuotedUTF8(OutputStream out) throws IOException;

    /**
     * Method for writing unescaped UTF-8 encoded String value using given
     * {@link java.io.OutputStream}.
     *
     * @param out {@link java.io.OutputStream} to write String into
     *
     * @return Number of bytes written
     *
     * @throws IOException if underlying stream write fails
     */
    int writeUnquotedUTF8(OutputStream out) throws IOException;

    /**
     * Method for appending JSON-escaped UTF-8 encoded String value into given
     * {@link java.nio.ByteBuffer}, if it fits.
     *
     * @param buffer {@link java.nio.ByteBuffer} to append String into
     *
     * @return Number of bytes put, if contents fit, otherwise -1
     *
     * @throws IOException if underlying buffer append operation fails
     */
    int putQuotedUTF8(ByteBuffer buffer) throws IOException;

    /**
     * Method for appending unquoted ('raw') UTF-8 encoded String value into given
     * {@link java.nio.ByteBuffer}, if it fits.
     *
     * @param buffer {@link java.nio.ByteBuffer} to append String into
     *
     * @return Number of bytes put, if contents fit, otherwise -1
     *
     * @throws IOException if underlying buffer append operation fails
     */
    int putUnquotedUTF8(ByteBuffer buffer) throws IOException;
}

⏎ com/fasterxml/jackson/core/SerializableString.java

Or download all of them as a single archive file:

File name: jackson-core-2.14.0-sources.jar
File size: 497693 bytes
Release date: 2022-11-05
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