testthread3.java

自己做的一个QQ聊天系统

package test.thread;

public class TestThread3 {
	public static void main(String[] args) throws InterruptedException {
		// TODO Auto-generated method stub
        TestSynchronized t = new TestSynchronized();
        t.add.start();
        t.sub.start();
        Thread.sleep(6000);
        System.out.println("i =" + t.i);
	}

}
class TestSynchronized{
	    int i = 200;
	    Thread add;
	    Thread sub;
	    public TestSynchronized(){
	    	 add = new Thread(){
	    		 public void run(){
	    			 for(int j=0;j<100;j++){
	    				 try{
	    					 Thread.sleep(50);
	    				 } catch (InterruptedException e) {
	    					 e.printStackTrace();
	    				 }
	    				 add();
	    			 }
	    		 }
	    		 
	    	 };
	    	 sub = new Thread(){
	    		 public void run(){
	    			 for(int j=0;j<100;j++){
	    				 try{
	    					 Thread.sleep(50);
	    				 } catch (InterruptedException e) {
	    					 e.printStackTrace();
	    				 }
	    				 sub();
	    			 }
	    		 }
	    	 };
	    	 
	    }
	    public synchronized void add(){
			i = i+1;
		}
		public synchronized void sub(){
			i = i-1;
		} 
}