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/WindowListener.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 window events.
 * The class that is interested in processing a window event
 * either implements this interface (and all the methods it
 * contains) or extends the abstract <code>WindowAdapter</code> class
 * (overriding only the methods of interest).
 * The listener object created from that class is then registered with a
 * Window using the window's <code>addWindowListener</code>
 * method. When the window's status changes by virtue of being opened,
 * closed, activated or deactivated, iconified or deiconified,
 * the relevant method in the listener object is invoked, and the
 * <code>WindowEvent</code> is passed to it.
 *
 * @author Carl Quinn
 *
 * @see WindowAdapter
 * @see WindowEvent
 * @see <a href="https://docs.oracle.com/javase/tutorial/uiswing/events/windowlistener.html">Tutorial: How to Write Window Listeners</a>
 *
 * @since 1.1
 */
public interface WindowListener extends EventListener {
    /**
     * Invoked the first time a window is made visible.
     */
    public void windowOpened(WindowEvent e);

    /**
     * Invoked when the user attempts to close the window
     * from the window's system menu.
     */
    public void windowClosing(WindowEvent e);

    /**
     * Invoked when a window has been closed as the result
     * of calling dispose on the window.
     */
    public void windowClosed(WindowEvent e);

    /**
     * Invoked when a window is changed from a normal to a
     * minimized state. For many platforms, a minimized window
     * is displayed as the icon specified in the window's
     * iconImage property.
     * @see java.awt.Frame#setIconImage
     */
    public void windowIconified(WindowEvent e);

    /**
     * Invoked when a window is changed from a minimized
     * to a normal state.
     */
    public void windowDeiconified(WindowEvent e);

    /**
     * Invoked when the Window is set to be the active Window. Only a Frame or
     * a Dialog can be the active Window. The native windowing system may
     * denote the active Window or its children with special decorations, such
     * as a highlighted title bar. The active Window is always either the
     * focused Window, or the first Frame or Dialog that is an owner of the
     * focused Window.
     */
    public void windowActivated(WindowEvent e);

    /**
     * Invoked when a Window is no longer the active Window. Only a Frame or a
     * Dialog can be the active Window. The native windowing system may denote
     * the active Window or its children with special decorations, such as a
     * highlighted title bar. The active Window is always either the focused
     * Window, or the first Frame or Dialog that is an owner of the focused
     * Window.
     */
    public void windowDeactivated(WindowEvent e);
}

⏎ java/awt/event/WindowListener.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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