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/MouseListener.java

/*
 * Copyright (c) 1996, 2013, 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 "interesting" mouse events
 * (press, release, click, enter, and exit) on a component.
 * (To track mouse moves and mouse drags, use the
 * <code>MouseMotionListener</code>.)
 * <P>
 * The class that is interested in processing a mouse event
 * either implements this interface (and all the methods it
 * contains) or extends the abstract <code>MouseAdapter</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>addMouseListener</code>
 * method. A mouse event is generated when the mouse is pressed, released
 * clicked (pressed and released). A mouse event is also generated when
 * the mouse cursor enters or leaves a component. When a mouse event
 * occurs, the relevant method in the listener object is invoked, and
 * the <code>MouseEvent</code> is passed to it.
 *
 * @author Carl Quinn
 *
 * @see MouseAdapter
 * @see MouseEvent
 * @see <a href="https://docs.oracle.com/javase/tutorial/uiswing/events/mouselistener.html">Tutorial: Writing a Mouse Listener</a>
 *
 * @since 1.1
 */
public interface MouseListener extends EventListener {

    /**
     * Invoked when the mouse button has been clicked (pressed
     * and released) on a component.
     */
    public void mouseClicked(MouseEvent e);

    /**
     * Invoked when a mouse button has been pressed on a component.
     */
    public void mousePressed(MouseEvent e);

    /**
     * Invoked when a mouse button has been released on a component.
     */
    public void mouseReleased(MouseEvent e);

    /**
     * Invoked when the mouse enters a component.
     */
    public void mouseEntered(MouseEvent e);

    /**
     * Invoked when the mouse exits a component.
     */
    public void mouseExited(MouseEvent e);
}

⏎ java/awt/event/MouseListener.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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