多生产-多消费

import java.util.concurrent.locks.*; // 1.5版本lock代替synchronized
// 资源
class Resource {
  // 首先私有数据，不直接对外暴露，只提供方法
  private String name; // 烤鸭name
  private int count = 1; // 烤鸭编号
  private boolean flag = false;
  // lock 互斥锁替代同步，当前lock运行，别的lock无法运行
  Lock lock = new ReentrantLock();
  // 获取该lock的监视器，可随意获取多个独立监视器用于特定需求，替代Object的wait notify notifyAll方法
  Condition producer_con = lock.newCondition(); 

  Condition consumer_con = lock.newCondition();

  public void newSet(String name) {
    lock.lock();
    try {
       // while...con.await 唤醒对方signal，不用All signalAll
    }
    finally {
      lock.unlock();
    }
  }
  // 生产与消费之间的线程需要等待唤醒，采用同步函数或同步代码块
  public synchronized void set(String name) {
     while(flag)  // 唤醒下面wait后的线程，每次都要再 try 一下判断flag
         try{this.wait();}catch(InterruptedException e){} // wait 方法需要声明或捕捉异常
     this.name = name + count；
     count++;
     Sop(Thread.cuuentThread().getName()+"...生产者..."+this.name);
     flag = true;
     notifyAll();  // 全唤醒避免死锁，由于flag必定唤醒对方线程
  }
  public synchronized void out() {
    while(!flag)
         try{this.wait();}catch(InterruptedException e){}
     Sop(Thread.cuuentThread().getName()+"...消费者..."+this.name);
     flag = false;
     notifyAll();
  }
}

class Producer implements Runnable {
     private Resource r;
     Producer(Resource r) {  // 初始化
       this.r = r;
     }
     public void run() {
       while(true) {  // 使劲生产
            r.set("烤鸭"); 
        }
     }
}

class Consumer implements Runnable {
     private Resource r;
     Consumer(Resource r) {  // 初始化
       this.r = r;
     }
     public void run() {
        while(true) {  // 使劲消费
            r.out(); 
        }
     }
}

class {
  public static void main(String[] args) {
    Resource r = new Resource();
    Producer pro = new Producer(r);
    Consumer con = new Consumer(r); 
    // 两个负责生产，两个负责消费
    Thread t0 = new Thread(pro);  
    Thread t1 = new Thread(pro);
    Thread t2 = new Thread(con);
    Thread t3 = new Thread(con);
    t0.start();
    t1.start();
    t2.start();
    t3.start();
  }  
}