java例程练习（多线程综合练习[生产者-消费者问题]）

/*
* 生产者与消费者问题
* 此问题用到Object类的wait(),notify()
* 还要注意一个问题：
* sleep()与wait()的区别：
* 		sleep()过程中，对象仍未解锁
* 		wait ()过程中，对象解锁，其他线程可以访问当前对象，当唤醒时需重新锁定
*/
public class Test {
public static void main(String[] args) {
ThingsStack ts = new ThingsStack();
Producer p = new Producer(ts);
Consumer c = new Consumer(ts);
new Thread(p).start();
new Thread(p).start();
new Thread(p).start();

new Thread(c).start();
new Thread(c).start();
new Thread(c).start();
}
}

class Things {
int id;
Things(int id) {
this.id = id;
}

public String toString() {
return "Things :" + id;
}
}

class ThingsStack {
int index = 0;
Things [] arrThings = new Things[6];

public synchronized void push(Things t) {

//if被打断后会跳出继续执行，用while语句更安全
//		if(index == arrThings.length) {
//			try {
//				this.wait();//Object类的wait();
//			} catch(InterruptedException e) {
//				e.printStackTrace();
//			}
//		}

while(index == arrThings.length) {
try {
this.wait();//Object类的wait();
} catch(InterruptedException e) {
e.printStackTrace();
}
}

//this.notify();
this.notifyAll();
arrThings[index] = t;
index ++;
}

public synchronized Things pop() {
//if被打断后会跳出继续执行，用while语句更安全
//		if(index == 0) {
//			try {
//				this.wait();//Object类的wait();
//			} catch(InterruptedException e) {
//				e.printStackTrace();
//			}
//		}

while(index == 0) {
try {
this.wait();//Object类的wait();
} catch(InterruptedException e) {
e.printStackTrace();
}
}

//this.notify();
this.notifyAll();

index --;
return arrThings[index];
}
}

class Producer implements Runnable {
ThingsStack ts = null;

Producer(ThingsStack ts) {
this.ts = ts;
}

public void run() {
for(int i = 0; i < 20; i++) {
Things t = new Things(i);
ts.push(t);

System.out.println("正在生产：" + t);

try {
Thread.sleep((int)Math.random() * 1000);
} catch(InterruptedException e) {
e.printStackTrace();
}

}
}
}

class Consumer implements Runnable {
ThingsStack ts = null;

Consumer(ThingsStack ts) {
this.ts = ts;
}

public void run() {
for(int i = 0; i < 20; i++) {
Things t = ts.pop();

System.out.println("正在消费：" + t);

try {
Thread.sleep((int)Math.random() * 1000);
} catch(InterruptedException e) {
e.printStackTrace();
}

}
}
}