只唤醒对方

忘是亡心i 2022-08-09 09:48 78阅读 0赞

package comm;
    
    import java.util.concurrent.locks.Condition;
    import java.util.concurrent.locks.Lock;
    import java.util.concurrent.locks.ReentrantLock;
    
    public class ProducerConsumerDemo2 {
    
        public static void main(String[] args) {
            Resource r = new Resource();
            Producer pro = new Producer(r);
            Consumer con = new Consumer(r);
    
            Thread t1 = new Thread(pro);
            Thread t2 = new Thread(pro);
            Thread t3 = new Thread(con);
            Thread t4 = new Thread(con);
    
            t1.start();
            t2.start();
            t3.start();
            t4.start();
    
        }
    }
    
    class Resource {
        private String name;
        private int count = 1;
        private boolean flag = false;
    
        private Lock lock = new ReentrantLock();
        private Condition condition_pro = lock.newCondition();
        private Condition condition_con = lock.newCondition();
    
        public void set(String name) throws InterruptedException {
    
            lock.lock();
            try {
                while (flag)
                    condition_pro.await();
                this.name = name + "==" + (count++);
                System.out.println(Thread.currentThread().getName()
                        + "==producer==" + this.name);
                flag = true;
                condition_con.signal(); // 唤醒对方
            } finally {
                lock.unlock();
            }
        }
    
        public void out() throws InterruptedException {
            lock.lock();
            try {
                while (!flag)
                    condition_con.await();
                System.out.println(Thread.currentThread().getName()
                        + "====consumer====" + this.name);
                flag = false;
                condition_pro.signal(); // 唤醒对方
            } finally {
                lock.unlock();
            }
        }
    }
    
    class Producer implements Runnable {
        private Resource res;
    
        Producer(Resource res) {
            this.res = res;
        }
    
        public void run() {
            while (true) {
                try {
                    res.set("+商品+");
                } catch (InterruptedException e) {
                }
            }
        }
    }
    
    class Consumer implements Runnable {
        private Resource res;
    
        Consumer(Resource res) {
            this.res = res;
        }
    
        public void run() {
            while (true)
                try {
                    res.out();
                } catch (InterruptedException e) {
                }
        }
    }