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Simple Timer

I am using a mouseListener to detect mouse movement on a page (code attached).  I would like a simple timer that counts down from X seconds, but resets every time the mouse is moved.  For example, it counts down from 45 seconds, but resets back to 45 and starts the countdown again when the mouse moves.  The applet code is attached as a snippet.  

import java.awt.*;
import java.awt.event.*;
import java.applet.*;
 
/*
  <applet code="MouseEvents" width=300 height=100>
  </applet>
*/
 
public class MouseEvents extends Applet
	implements MouseListener, MouseMotionListener {
	
	String msg = " ";
	int mouseX = 0, mouseY = 0;
 
	public void init() {
		addMouseListener(this);
		addMouseMotionListener(this);
	}
 
	public void mouseClicked(MouseEvent me) {
		mouseX= 0;
		mouseY = 10;
		repaint();
	}
 
	public void mouseEntered(MouseEvent me) {
		mouseX = 0;
		mouseY = 10;
		repaint();
	}
 
	public void mouseExited(MouseEvent me) {
		mouseX = 0;
		mouseY = 10;
		repaint();
	}
 
	public void mousePressed(MouseEvent me) {
		mouseX = me.getX();
		mouseY = me.getY();
		repaint();
	}
 
	public void mouseReleased(MouseEvent me) {
		mouseX = me.getX();
		mouseY = me.getY();
		repaint();
	}
 
	public void mouseDragged(MouseEvent me) {
		mouseX = me.getX();
		mouseY = me.getY();
		showStatus("Dragging mouse at " + mouseX + ", " + mouseY);
		repaint();
	}
 
	public void mouseMoved(MouseEvent me) {
		showStatus("Moving mouse at " + me.getX() + ", " + me.getY());
	}
 
	public void paint(Graphics g) {
		g.drawString(msg, mouseX, mouseY);
	}
}

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ASKER CERTIFIED SOLUTION
Avatar of Bart Cremers
Bart Cremers
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ASKER

Thank you!!!!!
Avatar of CEHJ
What does the countdown do?
Ultimately, I would like the user to be redirected to another page after X seconds of inactivity have passed.  This timer works great...  but, of course, when I compile it using the older JDK so it will run on MSJVM (like in my last issue), I get an error :(

This MSJVM is a JOKE!
Why do you want it to run on MSJVM. Microsoft will stop spreading it anyway on december 31 this year. Most computers these days have a Sun JRE on the system anyway, so you could easily go for a Sun 1.5 or 1.6
Bart,

I know.  If it were up to me, all our machines would be using the Sun JRE.  However, one application that the company is using will not work properly on the current Sun JRE -- it only works in MSJVM.  Well, I should rephrase that:

The applet seems to work fine, but the JavaScript button that is supposed to export the applet data to an Excel sheet throws an error when running on Sun JRE.
Here's a 1.1 implementation:

import java.applet.Applet;
import java.awt.*;
import java.awt.event.*;

/*
  <applet code="MouseEvents" width=300 height=100>
  </applet>
*/

public class MouseEvents extends Applet
    implements MouseListener, MouseMotionListener, ActionListener {
    Timer timer;
    int mouseX = 0, mouseY = 0;
    private int count;

    public void init() {
        addMouseListener(this);
        addMouseMotionListener(this);

        timer = new Timer(1000, this);
        timer.start();
        count = 45;
    }

    public void mouseClicked(MouseEvent me) {
        mouseX = 0;
        mouseY = 10;
        repaint();
    }

    public void mouseEntered(MouseEvent me) {
        mouseX = 0;
        mouseY = 10;
        repaint();
    }

    public void mouseExited(MouseEvent me) {
        mouseX = 0;
        mouseY = 10;
        repaint();
    }

    public void mousePressed(MouseEvent me) {
        mouseX = me.getX();
        mouseY = me.getY();
        repaint();
    }

    public void mouseReleased(MouseEvent me) {
        mouseX = me.getX();
        mouseY = me.getY();
        repaint();
    }

    public void mouseDragged(MouseEvent me) {
        mouseX = me.getX();
        mouseY = me.getY();
        showStatus("Dragging mouse at " + mouseX + ", " + mouseY);
        repaint();
    }

    public void mouseMoved(MouseEvent me) {
        count = 45;
        timer.restart();
        showStatus("Moving mouse at " + me.getX() + ", " + me.getY());
        repaint();
    }

    public void paint(Graphics g) {
        g.drawString(String.valueOf(count), mouseX, mouseY);
    }

    public void actionPerformed(ActionEvent e) {
        count = Math.max(0, --count);
        repaint();
    }

    private class Timer extends Thread {
        private final int interval;
        private final ActionListener listener;
        private volatile boolean run = true;

        public Timer(int interval, ActionListener listener) {
            this.interval = interval;
            this.listener = listener;
        }

        public void restart() {
            interrupt();
        }

        public void stopTimer() {
            run = false;
            interrupt();
        }

        public void run() {
            while(run) {
                try {
                    Thread.sleep(interval);
                    listener.actionPerformed(new ActionEvent(this, 0, null));
                } catch (InterruptedException e) {
                    interrupted();
                }
            }
        }
    }
}
Bart,

You're awesome!  Thank you.  Here's a simple one for you:  how do I redirect the user to a different URL once the timer reaches 0?
           try {
                getAppletContext().showDocument(new URL("http://www.google.com"));
            } catch (MalformedURLException e1) {
                // Ignore
            }



http://tns-www.lcs.mit.edu/manuals/java-api-1.1beta2/api/java.applet.AppletContext.html#showDocument(java.net.URL,%20java.lang.String)
I get two errors:
----------------------
MouseEvents.java:79: cannot resolve symbol
symbol  : class URL
location: class MouseEvents
                                getAppletContext().showDoc
www.google.com"));

MouseEvents.java:81: cannot resolve symbol
symbol  : class MalformedURLException
location: class MouseEvents
                        catch (MalformedURLException e1)
                               ^
2 errors
----------------------
I may be putting it in the wrong place...  I'm putting it within an IF statement:
public void actionPerformed(ActionEvent e) {
        count = Math.max(0, --count);
        repaint();

            if (count == 0) try
                  {
                        getAppletContext().showDocument(new URL("http://www.google.com"));
                  }
                  catch (MalformedURLException e1)
                  {
                        // Ignore
                  }
    }
Looks like a copy/paste problem to me. The compiler output shows some strange code.
I just tried again, and typed it this time.  Are the strange symbols you're talking about the ^ ?  I am compiling from a CMD window, I'm not sure if that has anything to do with it.  It's the only compiler I have (other than the current JDK).  Let me mess with it a bit.
Am I missing an "import" line?
No extra imports are needed here.
Wait! These imports are need:

import java.net.URL;
import java.net.MalformedURLException;
It worked!  Thank you!  I'm about 98% done with this darn thing.  I really appreciate the help, and you're taking the time to explain things.