生産者消費者模式實作

生産者消費者模式實作(synchronized、wait和notify方式)

一. 基本流程

生産者在緩沖區未滿時生産資料，消費者在緩沖區有資料時從緩沖區中取資料。

如果緩沖區已經滿了，則生産者線程阻塞；

如果緩沖區為空，那麼消費者線程阻塞。

二. 對象類型

1. 生産者
2. 消費者
3. 倉庫
4. 産品

三. 代碼實作

1. 産品

package xyz.yyaosen.produce;

import java.util.ArrayList;
import java.util.List;

public class Produce {
	// 緩沖區-産品
	private static List<Integer> produce = new ArrayList<Integer>();
	// 緩沖區-容量
	private static final int VOLUME = 10;
	// 狀态鎖
	private Object lock;

	public Produce() {
	}

	public Produce(Object lock) {
		// TODO Auto-generated constructor stub
		this.lock = lock;
	}

	// 生産
	public void add() {
		synchronized (lock) {
			if (produce.size() < VOLUME) {
				produce.add(1);
				System.out.println("生産者" + Thread.currentThread().getId() + ",産品數量(+1):" + produce.size());
				lock.notifyAll();
			} else {
				try {
					System.out
							.println("生産者" + Thread.currentThread().getId() + ",産品數量(/):" + produce.size() + "/等待...");
					lock.wait(1000);
				} catch (InterruptedException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
		}

	}

	// 消費
	public void remove() {

		synchronized (lock) {
			if (produce.size() > 0) {
				produce.remove(produce.size() - 1);
				System.out.println("消費者" + Thread.currentThread().getId() + ",産品數量(-1):" + produce.size());
				lock.notifyAll();
			} else {
				try {
					System.out
							.println("消費者" + Thread.currentThread().getId() + ",産品數量(/):" + produce.size() + "/等待...");
					lock.wait(1000);
				} catch (InterruptedException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
		}

	}
}

           

1. 消費者線程

package xyz.yyaosen.produce;

public class ConsumerThread implements Runnable {
	// 産品執行個體
	Produce produce = new Produce(new Object());

	// run
	public void run() {
		while (true) {
			produce.remove();
		}
	}
}
           

1. 生産者線程

package xyz.yyaosen.produce;

public class ProduceThread implements Runnable {
	// 産品執行個體
	Produce produce = new Produce(new Object());

	// run
	public void run() {
		while (true) {
			produce.add();
		}
	}
}
           

1. 入口類

package xyz.yyaosen.produce;

public class Test {

	public static void main(String[] args) {
		// TODO Auto-generated method stub
		// 消費者線程
		ConsumerThread consumerThread = new ConsumerThread();
		Thread cThread1 = new Thread(consumerThread);
		Thread cThread2 = new Thread(consumerThread);

		// 生産者線程
		ProduceThread produceThread = new ProduceThread();
		Thread pThread1 = new Thread(produceThread);
		Thread pThread2 = new Thread(produceThread);

		cThread1.start();
		cThread2.start();
		pThread1.start();
		pThread2.start();
	}
}
           

5.執行結果