多线程(1)

java 编程思想-- 继承自Thread :

package com.xtl.java;

public class test extends Thread{
	private int countDown = 6;
	private int threadCount = 0;
	private int threadNumber = ++threadCount;
	public  test(int a ){
		threadNumber = a;
		System.out.println("Making  " + threadNumber );
	}
	public void run(){
		while(true){
			System.out.println("Thread " + 
					threadNumber+"("+countDown+")");
			if(--countDown==0){ return ;}
		}
	}
	public static void main(String[] args){
		for(int i = 0;i<5; i++){
			new test(i).start();
		}
		System.out.println("All  Threads Started");
	}
}

　　 首先SimpleThread 继承了Thread 这个类，Thread 中最主要的是run (); 你必须覆写它，使线程执行你所指派的工作。因此run () 是程序中会和其他线程“同时”执行的部分。

　　run() 实际上具有某种形式的循环，此种循环会不断的执行，直到程序不再需要该线程为止。所以你必须设定此循环的脱离条件（或是和上例一样直接从run() 回返）。

package com.xtl.java;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.JApplet;

public class test extends JApplet{
	private class SeparateSubTask extends Thread{
		private int count = 0;
		private boolean runFlag = true;
		SeparateSubTask(){
			start();
		}
		void invertFlag() { 	
			runFlag = !runFlag;
		}
		
		public void run (){
			while(true){
				try{
					sleep(1000);
				}catch(InterruptedException e) {
					System.err.println("Interrupted");
				}
				if(runFlag)
				{
					t.setText(Integer.toString(count++));
				}
			}
		}
	}
		private SeparateSubTask sp = null;
		private JTextField t = new JTextField(10);
		private JButton start = new JButton("Start"),onOff = new JButton("Toggle");
		class StartL implements ActionListener {
			public  void actionPerformed(ActionEvent e){
				if(sp == null){
					sp = new SeparateSubTask();
				}
			}
		}
		
		class OnOffL implements ActionListener{
			public void actionPerformed(ActionEvent e){
				if(sp !=null){
					sp.invertFlag();
				}
			}
		}	
		public void init (){
			Container cp = getContentPane();
			cp.setLayout(new FlowLayout());
			cp.add(t);
			start.addActionListener(new StartL());
			cp.add(start);
			onOff.addActionListener(new OnOffL());
			cp.add(onOff);
		}
		public static void  main(String[] args){
			test t = new test();
			JFrame frame = new JFrame("test");
			frame.addWindowListener(new WindowAdapter(){
				public void windowClosing(WindowEvent e ){
					System.exit(0);
				}
			});
			frame.getContentPane().add(t);
			frame.setSize(300,100);
			t.init();
			t.start();
			frame.setVisible(true);
		}
}