package test;
/**
* 多生产者 多消费者问题
*
* 该代码存在死锁问题
* 因为有可能唤醒本方
* @author 黄二狗
*
*/
public class Test {
public static void main(String[] args) {
Resource r = new Resource();
Producer producer = new Producer(r);
Consumer consumer = new Consumer(r);
Thread t0 = new Thread(producer);
Thread t1 = new Thread(producer);
Thread t2 = new Thread(consumer);
Thread t3 = new Thread(consumer);
t0.start();
t1.start();
t2.start();
t3.start();
}
}
class Resource {
private String name;
private int count;
private boolean flag;
public synchronized void set(String name) throws InterruptedException {
while(flag)
this.wait(); // t0 t1
this.name = name + count;
count++;
System.out.println(Thread.currentThread().getName() + "....生产者..." + this.name);
flag = true;
this.notify();
}
public synchronized void out() throws InterruptedException {
while(!flag) //t2 t3
this.wait();
System.out.println(Thread.currentThread().getName() + "....消费者..." + this.name);
flag = false;
this.notify();
}
}
class Producer implements Runnable {
private Resource r;
public Producer(Resource r) {
this.r = r;
}
@Override
public void run() {
while(true) {
try {
r.set("烤鸭");
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
class Consumer implements Runnable {
private Resource r;
public Consumer(Resource r) {
this.r = r;
}
@Override
public void run() {
try {
while(true) {
r.out();
}
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
改进方法:将notify()换成notifyAll(),这样的话就不会产生死锁了.
package test;
/**
* 多生产者 多消费者问题
*
* 该代码存在死锁问题
* 因为有可能唤醒本方
* @author 黄二狗
*
*/
public class Test {
public static void main(String[] args) {
Resource r = new Resource();
Producer producer = new Producer(r);
Consumer consumer = new Consumer(r);
Thread t0 = new Thread(producer);
Thread t1 = new Thread(producer);
Thread t2 = new Thread(consumer);
Thread t3 = new Thread(consumer);
t0.start();
t1.start();
t2.start();
t3.start();
}
}
class Resource {
private String name;
private int count;
private boolean flag;
public synchronized void set(String name) throws InterruptedException {
while(flag)
this.wait(); // t0 t1
this.name = name + count;
count++;
System.out.println(Thread.currentThread().getName() + "....生产者..." + this.name);
flag = true;
this.notifyAll();
}
public synchronized void out() throws InterruptedException {
while(!flag) //t2 t3
this.wait();
System.out.println(Thread.currentThread().getName() + "....消费者..." + this.name);
flag = false;
this.notifyAll();
}
}
class Producer implements Runnable {
private Resource r;
public Producer(Resource r) {
this.r = r;
}
@Override
public void run() {
while(true) {
try {
r.set("烤鸭");
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}
class Consumer implements Runnable {
private Resource r;
public Consumer(Resource r) {
this.r = r;
}
@Override
public void run() {
try {
while(true) {
r.out();
}
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
原文:http://www.cnblogs.com/bean/p/7689908.html