//: Counter3.java ////////////////////////////////////////////////// // Copyright (c) Bruce Eckel, 1998 // Source code file from the book "Thinking in Java" // All rights reserved EXCEPT as allowed by the // following statements: You can freely use this file // for your own work (personal or commercial), // including modifications and distribution in // executable form only. Permission is granted to use // this file in classroom situations, including its // use in presentation materials, as long as the book // "Thinking in Java" is cited as the source. // Except in classroom situations, you cannot copy // and distribute this code; instead, the sole // distribution point is http://www.BruceEckel.com // (and official mirror sites) where it is // freely available. You cannot remove this // copyright and notice. You cannot distribute // modified versions of the source code in this // package. You cannot use this file in printed // media without the express permission of the // author. Bruce Eckel makes no representation about // the suitability of this software for any purpose. // It is provided "as is" without express or implied // warranty of any kind, including any implied // warranty of merchantability, fitness for a // particular purpose or non-infringement. The entire // risk as to the quality and performance of the // software is with you. Bruce Eckel and the // publisher shall not be liable for any damages // suffered by you or any third party as a result of // using or distributing software. In no event will // Bruce Eckel or the publisher be liable for any // lost revenue, profit, or data, or for direct, // indirect, special, consequential, incidental, or // punitive damages, however caused and regardless of // the theory of liability, arising out of the use of // or inability to use software, even if Bruce Eckel // and the publisher have been advised of the // possibility of such damages. Should the software // prove defective, you assume the cost of all // necessary servicing, repair, or correction. If you // think you've found an error, please email all // modified files with clearly commented changes to: // Bruce@EckelObjects.com. (Please use the same // address for non-code errors found in the book.) ///////////////////////////////////////////////// // Using the Runnable interface to turn the // main class into a thread. import java.awt.*; import java.awt.event.*; import java.applet.*; public class Counter3 extends Applet implements Runnable { private int count = 0; private boolean runFlag = true; private Thread selfThread = null; private Button onOff = new Button("Toggle"), start = new Button("Start"); private TextField t = new TextField(10); public void init() { add(t); start.addActionListener(new StartL()); add(start); onOff.addActionListener(new OnOffL()); add(onOff); } public void run() { while (true) { try { selfThread.sleep(100); } catch (InterruptedException e){} if(runFlag) t.setText(Integer.toString(count++)); } } class StartL implements ActionListener { public void actionPerformed(ActionEvent e) { if(selfThread == null) { selfThread = new Thread(Counter3.this); selfThread.start(); } } } class OnOffL implements ActionListener { public void actionPerformed(ActionEvent e) { runFlag = !runFlag; } } public static void main(String[] args) { Counter3 applet = new Counter3(); Frame aFrame = new Frame("Counter3"); aFrame.addWindowListener( new WindowAdapter() { public void windowClosing(WindowEvent e) { System.exit(0); } }); aFrame.add(applet, BorderLayout.CENTER); aFrame.setSize(300,200); applet.init(); applet.start(); aFrame.setVisible(true); } } ///:~