线程协作,producer and consumer.

//Q.java 代表队列，存数据

package com.test.threadcooperate;

//A correct implementation of a producer and consumer.
public class Q {
int n;
volatile boolean valueSet = false;

public synchronized int get() {
if (!valueSet)
try {
wait(); // 无限等待
// wait(4000); //每过4秒继续执行一次
} catch (InterruptedException e) {
System.out.println("InterruptedException caught");
}
System.out.println(Thread.currentThread() + ",ThreadID:"
+ Thread.currentThread().getId() + " Got: " + n);
valueSet = false;
notifyAll();
return n;
}

synchronized void put(int n) {
if (valueSet)
try {
wait();
} catch (InterruptedException e) {
System.out.println("InterruptedException caught");
}
this.n = n;
valueSet = true;
System.out.println("Put: " + n);
notifyAll();
}
}

//producer.java
package com.test.threadcooperate;

public class Producer implements Runnable {
Q q;

Producer(Q q) {
this.q = q;
new Thread(this, "Producer").start();
}

public void run() {
int i = 0;
//		while (true) {
//			q.put(i++);
//		}
for(;i<100;) {
q.put(i++);
}
q.put(-1);	//用于退出，状态标志
}
}

//consumer.java

package com.test.threadcooperate;

public class Consumer implements Runnable {
Q q;

Consumer(Q q) {
this.q = q;
new Thread(this, "Consumer").start();
}

public void run() {
while (true) {
int result= q.get();
if(result==-1)break;
}
}
}

//PCFixed.java

package com.test.threadcooperate;

public class PCFixed {

/**
* @param args
*/
public static void main(String[] args) {
Q q = new Q();
new Producer(q);
new Consumer(q);	//消费者1
//		new Consumer(q);	//消费者2,有两个消费者时有问题。
System.out.println("Press Control-C to stop.");
}
}