wait-notifyAll实现生产者与消费者模型

雨点打透心脏的1/2处 2022-01-27 14:23 184阅读 0赞

## 前述 ##

*  生产者与消费者问题是线程并发问题中一个重要的内容，java有多种实现方式，而利用线程wait和notifyAll可以简单实现生产与消费并发的思想。
 *  关键在于一个公共缓冲区用于存储当前生产的产品，生产和消费对同一个仓库（缓冲区）进行操作，这里使用LinkedList来模拟一个公共缓冲区，每次对缓冲区的操作都是从队尾进行添加删除。

## 代码区 ##

package produce_consumer;
    
    
    import java.util.Date;
    import java.util.LinkedList;
    import java.util.List;
    
    /*
     * 仓库模型
     */
    public class Storage {
    
    	private static int maxsize;
    	private static List<Date> storage;
    	
    	public Storage() {
    		maxsize = 10;
    		storage = new LinkedList<Date>();
    		
    	}
    	
    	public synchronized void set() {
    		if(storage.size() == maxsize) {
    			try {
    				wait();
    			}catch(InterruptedException e) {
    			    e.printStackTrace();
    			}
    		}
    		storage.add(new Date());
    		System.out.println("product:"+storage.size());
    		notifyAll();
    	}
    	
    	public synchronized void get() {
    		if(storage.size() == 0 ) {
    			
    		    try {
    				wait();
    			} catch (InterruptedException e) 
    		    {
    				e.printStackTrace();
    			}	
    		}
    		
    		System.out.println("Consumer:第"+storage.size()+"个 ： "+((LinkedList<?>)storage).poll());
    		
    		notifyAll();
    	
    	}
    }

package produce_consumer;
    
    /*
     * 生产者
     */
    public class Producer implements Runnable{
    
    	private Storage storage;
    	public Producer(Storage storage) {
    		this.storage = storage;
    	}
    	
    	public void run() {
    		for(int i=0; i<10; i++) {
    			storage.set();
    		}
    		
    	}
    }

package produce_consumer;
    
    /*
     * 消费者
     */
    public class Consumer implements Runnable{
    
    	private Storage storage;
    	public Consumer(Storage storage) {
    		this.storage = storage;
    	}
    	
    	public void run() {
    		for(int i=0; i<10; i++) {
    			storage.get();
    		}
    	}
    	
    }

package produce_consumer;
    
    public class MainThread {
    
    	public static void main(String[] args) {
    		Storage storage = new Storage();
    		Producer producer = new Producer(storage);
    		//生产者线程
    		Thread thread1 = new Thread(producer);
    		
    		Consumer consumer = new Consumer(storage);
    		//消费者线程
    		Thread thread2 = new Thread(consumer);
    		
    		thread1.start();
    		thread2.start();
    
    	}
    
    }