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/event/KeyListener.java

/*
 * Copyright (c) 1996, 2014, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
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package java.awt.event;

import java.util.EventListener;

/**
 * The listener interface for receiving keyboard events (keystrokes).
 * The class that is interested in processing a keyboard event
 * either implements this interface (and all the methods it
 * contains) or extends the abstract <code>KeyAdapter</code> class
 * (overriding only the methods of interest).
 * <P>
 * The listener object created from that class is then registered with a
 * component using the component's <code>addKeyListener</code>
 * method. A keyboard event is generated when a key is pressed, released,
 * or typed. The relevant method in the listener
 * object is then invoked, and the <code>KeyEvent</code> is passed to it.
 *
 * @author Carl Quinn
 *
 * @see KeyAdapter
 * @see KeyEvent
 * @see <a href="https://docs.oracle.com/javase/tutorial/uiswing/events/keylistener.html">Tutorial: Writing a Key Listener</a>
 *
 * @since 1.1
 */
public interface KeyListener extends EventListener {

    /**
     * Invoked when a key has been typed.
     * See the class description for {@link KeyEvent} for a definition of
     * a key typed event.
     */
    public void keyTyped(KeyEvent e);

    /**
     * Invoked when a key has been pressed.
     * See the class description for {@link KeyEvent} for a definition of
     * a key pressed event.
     */
    public void keyPressed(KeyEvent e);

    /**
     * Invoked when a key has been released.
     * See the class description for {@link KeyEvent} for a definition of
     * a key released event.
     */
    public void keyReleased(KeyEvent e);
}

⏎ java/awt/event/KeyListener.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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