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 javax.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ javax/swing/event/InternalFrameEvent.java

/*
 * Copyright (c) 1998, 2013, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
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 *
 *
 *
 *
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 *
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 *
 *
 *
 *
 */
package javax.swing.event;

import java.awt.AWTEvent;
import javax.swing.JInternalFrame;

/**
 * An <code>AWTEvent</code> that adds support for
 * <code>JInternalFrame</code> objects as the event source.  This class has the
 * same event types as <code>WindowEvent</code>,
 * although different IDs are used.
 * Help on handling internal frame events
 * is in
 * <a href="https://docs.oracle.com/javase/tutorial/uiswing/events/internalframelistener.html" target="_top">How to Write an Internal Frame Listener</a>,
 * a section in <em>The Java Tutorial</em>.
 * <p>
 * <strong>Warning:</strong>
 * Serialized objects of this class will not be compatible with
 * future Swing releases. The current serialization support is
 * appropriate for short term storage or RMI between applications running
 * the same version of Swing.  As of 1.4, support for long term storage
 * of all JavaBeans&trade;
 * has been added to the <code>java.beans</code> package.
 * Please see {@link java.beans.XMLEncoder}.
 *
 * @see java.awt.event.WindowEvent
 * @see java.awt.event.WindowListener
 * @see JInternalFrame
 * @see InternalFrameListener
 *
 * @author Thomas Ball
 */
public class InternalFrameEvent extends AWTEvent {

    /**
     * The first number in the range of IDs used for internal frame events.
     */
    public static final int INTERNAL_FRAME_FIRST        = 25549;

    /**
     * The last number in the range of IDs used for internal frame events.
     */
    public static final int INTERNAL_FRAME_LAST         = 25555;

    /**
     * The "window opened" event.  This event is delivered only
     * the first time the internal frame is made visible.
     *
     * @see JInternalFrame#show
     */
    public static final int INTERNAL_FRAME_OPENED       = INTERNAL_FRAME_FIRST;

    /**
     * The "window is closing" event. This event is delivered when
     * the user attempts to close the internal frame, such as by
     * clicking the internal frame's close button,
     * or when a program attempts to close the internal frame
     * by invoking the <code>setClosed</code> method.
     *
     * @see JInternalFrame#setDefaultCloseOperation
     * @see JInternalFrame#doDefaultCloseAction
     * @see JInternalFrame#setClosed
     */
    public static final int INTERNAL_FRAME_CLOSING      = 1 + INTERNAL_FRAME_FIRST;

    /**
     * The "window closed" event. This event is delivered after
     * the internal frame has been closed as the result of a call to
     * the <code>setClosed</code> or
     * <code>dispose</code> method.
     *
     * @see JInternalFrame#setClosed
     * @see JInternalFrame#dispose
     */
    public static final int INTERNAL_FRAME_CLOSED       = 2 + INTERNAL_FRAME_FIRST;

    /**
     * The "window iconified" event.
     * This event indicates that the internal frame
     * was shrunk down to a small icon.
     *
     * @see JInternalFrame#setIcon
     */
    public static final int INTERNAL_FRAME_ICONIFIED    = 3 + INTERNAL_FRAME_FIRST;

    /**
     * The "window deiconified" event type. This event indicates that the
     * internal frame has been restored to its normal size.
     *
     * @see JInternalFrame#setIcon
     */
    public static final int INTERNAL_FRAME_DEICONIFIED  = 4 + INTERNAL_FRAME_FIRST;

    /**
     * The "window activated" event type. This event indicates that keystrokes
     * and mouse clicks are directed towards this internal frame.
     *
     * @see JInternalFrame#show
     * @see JInternalFrame#setSelected
     */
    public static final int INTERNAL_FRAME_ACTIVATED    = 5 + INTERNAL_FRAME_FIRST;

    /**
     * The "window deactivated" event type. This event indicates that keystrokes
     * and mouse clicks are no longer directed to the internal frame.
     *
     * @see JInternalFrame#setSelected
     */
    public static final int INTERNAL_FRAME_DEACTIVATED  = 6 + INTERNAL_FRAME_FIRST;

    /**
     * Constructs an <code>InternalFrameEvent</code> object.
     * @param source the <code>JInternalFrame</code> object that originated the event
     * @param id     an integer indicating the type of event
     */
    public InternalFrameEvent(JInternalFrame source, int id) {
        super(source, id);
    }

    /**
     * Returns a parameter string identifying this event.
     * This method is useful for event logging and for debugging.
     *
     * @return a string identifying the event and its attributes
     */
    public String paramString() {
        String typeStr;
        switch(id) {
          case INTERNAL_FRAME_OPENED:
              typeStr = "INTERNAL_FRAME_OPENED";
              break;
          case INTERNAL_FRAME_CLOSING:
              typeStr = "INTERNAL_FRAME_CLOSING";
              break;
          case INTERNAL_FRAME_CLOSED:
              typeStr = "INTERNAL_FRAME_CLOSED";
              break;
          case INTERNAL_FRAME_ICONIFIED:
              typeStr = "INTERNAL_FRAME_ICONIFIED";
              break;
          case INTERNAL_FRAME_DEICONIFIED:
              typeStr = "INTERNAL_FRAME_DEICONIFIED";
              break;
          case INTERNAL_FRAME_ACTIVATED:
              typeStr = "INTERNAL_FRAME_ACTIVATED";
              break;
          case INTERNAL_FRAME_DEACTIVATED:
              typeStr = "INTERNAL_FRAME_DEACTIVATED";
              break;
          default:
              typeStr = "unknown type";
        }
        return typeStr;
    }


    /**
     * Returns the originator of the event.
     *
     * @return the <code>JInternalFrame</code> object that originated the event
     * @since 1.3
     */

    public JInternalFrame getInternalFrame () {
      return (source instanceof JInternalFrame)? (JInternalFrame)source : null;
    }


}

⏎ javax/swing/event/InternalFrameEvent.java

Or download all of them as a single archive file:

File name: jre-rt-javax-1.8.0_191-src.zip
File size: 5381005 bytes
Release date: 2018-10-28
Download 

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⇐ JRE 8 rt.jar - java.* Package Source Code

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