生产者与消费者例子(多线程wait()与notifyAll应用)

package test;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

class Meal {
	private final int orderNum;

	public Meal(int orderNum) {
		this.orderNum = orderNum;
	}

	public String toString() {
		return "Meal " + orderNum;
	}
}
class WaitPerson implements Runnable{
	private Restaurant restaurant;
	public WaitPerson(Restaurant r){
		restaurant=r;
	}
	@Override
	public void run() {
		try {
			while(!Thread.interrupted()){
				synchronized (this) {
					while(restaurant.meal==null){
						wait();
					}
					
				}
				System.out.println("Waitperson got "+restaurant.meal);
				synchronized(restaurant.chef){
					restaurant.meal=null;
					restaurant.chef.notifyAll();
				}
			}
		} catch (InterruptedException e) {
			System.out.println("Waitperson interrupted");
		}
		
	}
	
}
class Chef implements Runnable{
	private Restaurant restaurant;
	private int count=0;
	public Chef(Restaurant r) {
		restaurant=r;
	}

	@Override
	public void run() {
		try {
			while(!Thread.interrupted()){
				synchronized (this) {//
					while(restaurant.meal!=null){
						wait();//
					}
				}
				if(++count==10){
					System.out.println("out of food, closing");
					restaurant.exec.shutdownNow();
				}
				System.out.print("Order up!");
				synchronized(restaurant.waitPerson){
					restaurant.meal=new Meal(count);
					restaurant.waitPerson.notifyAll();
				}
				TimeUnit.MILLISECONDS.sleep(100);
			}
		} catch (InterruptedException e) {
			System.out.println("Chef interrupted");
		}
		
	}
	
}
public class Restaurant {

	/**
	 * @param args
	 */
	Meal meal;
	ExecutorService exec=Executors.newCachedThreadPool();
	WaitPerson waitPerson=new WaitPerson(this);
	Chef chef=new Chef(this);
	public Restaurant(){
		exec.execute(chef);//启动chef线程
		exec.execute(waitPerson);//启动waitPerson线程
	}
	public static void main(String[] args) {
		new Restaurant();

	}

}