七、多个线程间共享数据的应用

/**

* 七、多个线程间共享数据的应用

*

* @author dahai

* 实例：设计4个线程，其中两个线程每次对j增加1，另外两个线程每次对j减少1，写出程序。

*/

public class MultiThreadShareData {

public static void main(String[] args) {

// TODO Auto-generated method stub

ShareData data = new ShareData();

//方式一、

new Thread(new MyRunnable1(data)).start();

new Thread(new MyRunnable2(data)).start();

//方式二、

new Thread(new Runnable() {

@Override

public void run() {

// TODO Auto-generated method stub

while (true) {

try {

Thread.sleep(1000);

} catch (InterruptedException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

data.decrement();

}

}

}).start();

new Thread(new Runnable() {

@Override

public void run() {

// TODO Auto-generated method stub

while (true) {

try {

Thread.sleep(1000);

} catch (InterruptedException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}

data.increment();

}

}

}).start();

}

}

class MyRunnable1 implements Runnable{

private ShareData data;

public MyRunnable1(ShareData data){

this.data = data;

}

@Override

public void run() {

// TODO Auto-generated method stub

data.decrement();

}

}

class MyRunnable2 implements Runnable{

private ShareData data;

public MyRunnable2(ShareData data){

this.data = data;

}

@Override

public void run() {

// TODO Auto-generated method stub

data.increment();

}

}

class ShareData {

private int j = 0;

public synchronized void increment() {

j++;

System.out.println("increment:"+j);

}

public synchronized void decrement() {

j--;

System.out.println("decrement:"+j);

}

}