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/Autoscroller.java

/*
 * Copyright (c) 1997, 2006, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 *
 */

package javax.swing;

import java.awt.*;
import java.awt.event.*;

import sun.awt.AWTAccessor;
import sun.awt.AWTAccessor.MouseEventAccessor;

/**
 * Autoscroller is responsible for generating synthetic mouse dragged
 * events. It is the responsibility of the Component (or its MouseListeners)
 * that receive the events to do the actual scrolling in response to the
 * mouse dragged events.
 *
 * @author Dave Moore
 * @author Scott Violet
 */
class Autoscroller implements ActionListener {
    /**
     * Global Autoscroller.
     */
    private static Autoscroller sharedInstance = new Autoscroller();

    // As there can only ever be one autoscroller active these fields are
    // static. The Timer is recreated as necessary to target the appropriate
    // Autoscroller instance.
    private static MouseEvent event;
    private static Timer timer;
    private static JComponent component;

    //
    // The public API, all methods are cover methods for an instance method
    //
    /**
     * Stops autoscroll events from happening on the specified component.
     */
    public static void stop(JComponent c) {
        sharedInstance._stop(c);
    }

    /**
     * Stops autoscroll events from happening on the specified component.
     */
    public static boolean isRunning(JComponent c) {
        return sharedInstance._isRunning(c);
    }

    /**
     * Invoked when a mouse dragged event occurs, will start the autoscroller
     * if necessary.
     */
    public static void processMouseDragged(MouseEvent e) {
        sharedInstance._processMouseDragged(e);
    }


    Autoscroller() {
    }

    /**
     * Starts the timer targeting the passed in component.
     */
    private void start(JComponent c, MouseEvent e) {
        Point screenLocation = c.getLocationOnScreen();

        if (component != c) {
            _stop(component);
        }
        component = c;
        event = new MouseEvent(component, e.getID(), e.getWhen(),
                               e.getModifiers(), e.getX() + screenLocation.x,
                               e.getY() + screenLocation.y,
                               e.getXOnScreen(),
                               e.getYOnScreen(),
                               e.getClickCount(), e.isPopupTrigger(),
                               MouseEvent.NOBUTTON);
        MouseEventAccessor meAccessor = AWTAccessor.getMouseEventAccessor();
        meAccessor.setCausedByTouchEvent(event,
            meAccessor.isCausedByTouchEvent(e));

        if (timer == null) {
            timer = new Timer(100, this);
        }

        if (!timer.isRunning()) {
            timer.start();
        }
    }

    //
    // Methods mirror the public static API
    //

    /**
     * Stops scrolling for the passed in widget.
     */
    private void _stop(JComponent c) {
        if (component == c) {
            if (timer != null) {
                timer.stop();
            }
            timer = null;
            event = null;
            component = null;
        }
    }

    /**
     * Returns true if autoscrolling is currently running for the specified
     * widget.
     */
    private boolean _isRunning(JComponent c) {
        return (c == component && timer != null && timer.isRunning());
    }

    /**
     * MouseListener method, invokes start/stop as necessary.
     */
    private void _processMouseDragged(MouseEvent e) {
        JComponent component = (JComponent)e.getComponent();
        boolean stop = true;
        if (component.isShowing()) {
            Rectangle visibleRect = component.getVisibleRect();
            stop = visibleRect.contains(e.getX(), e.getY());
        }
        if (stop) {
            _stop(component);
        } else {
            start(component, e);
        }
    }

    //
    // ActionListener
    //
    /**
     * ActionListener method. Invoked when the Timer fires. This will scroll
     * if necessary.
     */
    public void actionPerformed(ActionEvent x) {
        JComponent component = Autoscroller.component;

        if (component == null || !component.isShowing() || (event == null)) {
            _stop(component);
            return;
        }
        Point screenLocation = component.getLocationOnScreen();
        MouseEvent e = new MouseEvent(component, event.getID(),
                                      event.getWhen(), event.getModifiers(),
                                      event.getX() - screenLocation.x,
                                      event.getY() - screenLocation.y,
                                      event.getXOnScreen(),
                                      event.getYOnScreen(),
                                      event.getClickCount(),
                                      event.isPopupTrigger(),
                                      MouseEvent.NOBUTTON);
        MouseEventAccessor meAccessor = AWTAccessor.getMouseEventAccessor();
        meAccessor.setCausedByTouchEvent(e,
            meAccessor.isCausedByTouchEvent(event));
        component.superProcessMouseMotionEvent(e);
    }

}

⏎ javax/swing/Autoscroller.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 

⇒ JRE 8 rt.jar - org.* Package Source Code

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

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