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/io/CharacterEscapes.java

package com.fasterxml.jackson.core.io;

import java.util.Arrays;

import com.fasterxml.jackson.core.SerializableString;

/**
 * Abstract base class that defines interface for customizing character
 * escaping aspects for String values, for formats that use escaping.
 * For JSON this applies to both property names and String values.
 */
@SuppressWarnings("serial")
public abstract class CharacterEscapes
    implements java.io.Serializable // since 2.1
{
    /**
     * Value used for lookup tables to indicate that matching characters
     * do not need to be escaped.
     */
    public final static int ESCAPE_NONE = 0;

    /**
     * Value used for lookup tables to indicate that matching characters
     * are to be escaped using standard escaping; for JSON this means
     * (for example) using "backslash - u" escape method.
     */
    public final static int ESCAPE_STANDARD = -1;

    /**
     * Value used for lookup tables to indicate that matching characters
     * will need custom escapes; and that another call
     * to {@link #getEscapeSequence} is needed to figure out exact escape
     * sequence to output.
     */
    public final static int ESCAPE_CUSTOM = -2;
    
    /**
     * Method generators can call to get lookup table for determining
     * escape handling for first 128 characters of Unicode (ASCII
     * characters. Caller is not to modify contents of this array, since
     * this is expected to be a shared copy.
     * 
     * @return Array with size of at least 128, where first 128 entries
     *    have either one of <code>ESCAPE_xxx</code> constants, or non-zero positive
     *    integer (meaning of which is data format specific; for JSON it means
     *    that combination of backslash and character with that value is to be used)
     *    to indicate that specific escape sequence is to be used.
     */
    public abstract int[] getEscapeCodesForAscii();

    /**
     * Method generators can call to get lookup table for determining
     * exact escape sequence to use for given character.
     * It can be called for any character, but typically is called for
     * either for ASCII characters for which custom escape
     * sequence is needed; or for any non-ASCII character.
     *
     * @param ch Character to look escape sequence for
     *
     * @return Escape sequence to use for the character, if any; {@code null} if not
     */
    public abstract SerializableString getEscapeSequence(int ch);

    /**
     * Helper method that can be used to get a copy of standard JSON
     * escape definitions; this is useful when just wanting to slightly
     * customize definitions. Caller can modify this array as it sees
     * fit and usually returns modified instance via {@link #getEscapeCodesForAscii}
     *
     * @return Set of escapes, similar to {@link #getEscapeCodesForAscii()} (array of
     *    128 {@code int}s), but a copy that caller owns and is free to modify
     */
    public static int[] standardAsciiEscapesForJSON()
    {
        int[] esc = CharTypes.get7BitOutputEscapes();
        return Arrays.copyOf(esc, esc.length);
    }
}

⏎ com/fasterxml/jackson/core/io/CharacterEscapes.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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