separatesubtask.java

java 数据结构的一些简单实例和一些线程的应用主要是面向初学者

import java.awt.*;
import java.awt.event.*;
import java.applet.*;
class SeparateSubTask extends Thread{
	private int count=0;
	private Counter2 c2;
	private boolean runflag=true;
	public SeparateSubTask(Counter2 c2){
		this.c2=c2;
		start();
	}
	public void invertflag(){runflag=!runflag;}
    public void run(){
    	while(true){
    		try{
    			sleep(100);
    		}catch(InterruptedException e){}
    		if(runflag)
    			c2.t.setText(Integer.toString(count++));
    	}
    }
}

class Counter2 extends Applet{
	TextField t=new TextField(10);
	private SeparateSubTask sp=null;
    private Button
    onoff=new Button("Toggle"),
    start=new Button("start");
    public void init(){
    	add(t);
    	start.addActionListener(new start());
    	add(start);
    	onoff.addActionListener(new onoff());
        add(onoff);
    }
    class start implements ActionListener{
    	public void actionPerformed(ActionEvent e){
    		if(sp==null)
    			sp=new SeparateSubTask(Counter2.this);
    	}
    }
    class onoff implements ActionListener{
    	public void actionPerformed(ActionEvent e){
    		if(sp!=null)
    			sp.invertflag();
    	}
    }
    public static void main(String[] args){
    	Counter2 applet=new Counter2();
    	Frame aFrame=new Frame("Counter2");
    	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);
    }
}