注意，一般使用notifyAll，如果使用notify，則只會通知一個wait的執行緒，notifyAll可防止通知訊號丟失 

package com.chapter1.ch1.wait;

public interface AbstractStorage {
	
	void consume(int num);
	
	void produce(int num);
	
}

package com.chapter1.ch1.wait;

import java.util.LinkedList;

public class Storage implements AbstractStorage {

	private static final int MAX_SIZE = 100;
	
	private LinkedList<Object> list = new LinkedList<Object>();
	
	
	/**
	 * 消費
	 */
	@Override
	public void consume(int num) {
		synchronized (list) {
			while (list != null && num > list.size()) {
				System.out.println("要消費【" + num + "】，但倉庫內只有" + "【" + list.size() + "】");
				
				try {
					list.wait();
				} catch (InterruptedException e) {
					e.printStackTrace();
				}
			}
			
			for (int i = 0; i < num; i++) {
				list.remove();
			}
			
			System.out.println("已要消費【" + num + "】，倉庫內剩餘" + "【" + list.size() + "】");
			
			// 通知生產方法上wait的執行緒不再wait
			list.notifyAll();
		}
	}

	@Override
	public void produce(int num) {
		synchronized (list) {
			while (list != null && (num + list.size()) > MAX_SIZE) {
				System.out.println("要生產【" + num + "】，但倉庫內已有" + "【" + list.size() + "】，生產後大於100");
				
				try {
					list.wait();
				} catch (InterruptedException e) {
					e.printStackTrace();
				}
			}
			
			for (int i = 0; i < num; i++) {
				list.add(new Object());
			}
			
			System.out.println("已生產【" + num + "】，倉庫內剩餘" + "【" + list.size() + "】");
			
			// 通知生產方法上wait的執行緒不再wait
			list.notifyAll();
		}
	}
	
}
 

package com.chapter1.ch1.wait;

public class Producer extends Thread {
	
	private int num;
	
	public AbstractStorage abstractStorage;
	
	public Producer(AbstractStorage abstractStorage) {
		this.abstractStorage = abstractStorage;
	}
	
	public void setNum(int num) {
		this.num = num;
	}
	
	
	public void produce(int num) {
		this.abstractStorage.produce(num);
	}
	
	
	@Override
	public void run() {
		
		produce(num);
		
	}
}
 

package com.chapter1.ch1.wait;

public class Consumer extends Thread {
	
	private int num;
	
	public AbstractStorage abstractStorage;
	
	public Consumer(AbstractStorage abstractStorage) {
		this.abstractStorage = abstractStorage;
	}
	
	public void setNum(int num) {
		this.num = num;
	}
	
	
	public void consumer(int num) {
		this.abstractStorage.consume(num);
	}
	
	
	@Override
	public void run() {
		
		consumer(num);
		
	}
}
 

package com.chapter1.ch1.wait;

public class WaitMain {
	
	
	public static void main(String[] args) {
		AbstractStorage storage = new Storage();
		
		Producer p1 = new Producer(storage);
		Producer p2 = new Producer(storage);
		Producer p3 = new Producer(storage);
		Producer p4 = new Producer(storage);
		
		p1.setNum(10);
		p2.setNum(10);
		p3.setNum(10);
		p4.setNum(80);
		
		Consumer c1 = new Consumer(storage);
		Consumer c2 = new Consumer(storage);
		Consumer c3 = new Consumer(storage);
		Consumer c4 = new Consumer(storage);
		
		c1.setNum(5);
		c2.setNum(5);
		c3.setNum(90);
		c4.setNum(1);
		
		try {
			p1.start();
			Thread.sleep(1000);
			p2.start();
			Thread.sleep(1000);
			p3.start();
			Thread.sleep(1000);
			p4.start();
			Thread.sleep(1000);
		} catch (InterruptedException e) {
			e.printStackTrace();
		}
		
		
		try {
			c1.start();
			Thread.sleep(2000);
			c2.start();
			Thread.sleep(2000);
			c3.start();
			Thread.sleep(2000);
			c4.start();
		} catch (InterruptedException e) {
			e.printStackTrace();
		}
		
	}
	
	
}