JRE 8 rt.jar is the JAR file for JRE 8 RT (Runtime) libraries. JRE (Java Runtime) 8 is the runtime environment included in JDK 8. JRE 8 rt.jar libraries are divided into 6 packages:

com.* - Internal Oracle and Sun Microsystems libraries
java.* - Standard Java API libraries.
javax.* - Extended Java API libraries.
jdk.* -  JDK supporting libraries.
org.* - Third party libraries.
sun.* - Old libraries developed by Sun Microsystems.

JAR File Information:

Directory of C:\fyicenter\jdk-1.8.0_191\jre\lib
      63,596,151 rt.jar

Here is the list of Java classes of the java.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ java/awt/im/InputSubset.java

/*
 * Copyright (c) 1998, 1999, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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 */

package java.awt.im;


/**
 * Defines additional Unicode subsets for use by input methods.  Unlike the
 * UnicodeBlock subsets defined in the <code>{@link
 * java.lang.Character.UnicodeBlock}</code> class, these constants do not
 * directly correspond to Unicode code blocks.
 *
 * @since   1.2
 */

public final class InputSubset extends Character.Subset {

    private InputSubset(String name) {
        super(name);
    }

    /**
     * Constant for all Latin characters, including the characters
     * in the BASIC_LATIN, LATIN_1_SUPPLEMENT, LATIN_EXTENDED_A,
     * LATIN_EXTENDED_B Unicode character blocks.
     */
    public static final InputSubset LATIN
        = new InputSubset("LATIN");

    /**
     * Constant for the digits included in the BASIC_LATIN Unicode character
     * block.
     */
    public static final InputSubset LATIN_DIGITS
        = new InputSubset("LATIN_DIGITS");

    /**
     * Constant for all Han characters used in writing Traditional Chinese,
     * including a subset of the CJK unified ideographs as well as Traditional
     * Chinese Han characters that may be defined as surrogate characters.
     */
    public static final InputSubset TRADITIONAL_HANZI
        = new InputSubset("TRADITIONAL_HANZI");

    /**
     * Constant for all Han characters used in writing Simplified Chinese,
     * including a subset of the CJK unified ideographs as well as Simplified
     * Chinese Han characters that may be defined as surrogate characters.
     */
    public static final InputSubset SIMPLIFIED_HANZI
        = new InputSubset("SIMPLIFIED_HANZI");

    /**
     * Constant for all Han characters used in writing Japanese, including a
     * subset of the CJK unified ideographs as well as Japanese Han characters
     * that may be defined as surrogate characters.
     */
    public static final InputSubset KANJI
        = new InputSubset("KANJI");

    /**
     * Constant for all Han characters used in writing Korean, including a
     * subset of the CJK unified ideographs as well as Korean Han characters
     * that may be defined as surrogate characters.
     */
    public static final InputSubset HANJA
        = new InputSubset("HANJA");

    /**
     * Constant for the halfwidth katakana subset of the Unicode halfwidth and
     * fullwidth forms character block.
     */
    public static final InputSubset HALFWIDTH_KATAKANA
        = new InputSubset("HALFWIDTH_KATAKANA");

    /**
     * Constant for the fullwidth ASCII variants subset of the Unicode halfwidth and
     * fullwidth forms character block.
     * @since 1.3
     */
    public static final InputSubset FULLWIDTH_LATIN
        = new InputSubset("FULLWIDTH_LATIN");

    /**
     * Constant for the fullwidth digits included in the Unicode halfwidth and
     * fullwidth forms character block.
     * @since 1.3
     */
    public static final InputSubset FULLWIDTH_DIGITS
        = new InputSubset("FULLWIDTH_DIGITS");

}

⏎ java/awt/im/InputSubset.java

Or download all of them as a single archive file:

File name: jre-rt-java-1.8.0_191-src.zip
File size: 6664831 bytes
Release date: 2018-10-28
Download 

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