生產者消費者---簡易消息隊列實現

目錄

 

1，場景

2，源碼

a）消息體

b）消息隊列

c）生產者

d）消費者

e）測試用例

f）結果輸出

---

1，場景

適用場景太多，不做描述。直接上源碼

2，源碼

a）消息體

package com.wayne.producerConsumer;

public class Message {
    
    private String data;
    
    public Message(String data){
        this.data = data;
    }

    public String getData() {
        return data;
    }
}

b）消息隊列

package com.wayne.producerConsumer;

import java.util.LinkedList;

public class MessageQueue {

    private final LinkedList<Message> queue;

    private final static int DEFAULT_QUEUE_SIZE = 100;

    private final int limit;

    public MessageQueue(){
        this(DEFAULT_QUEUE_SIZE);
    }

    public MessageQueue(int limit){
        this.limit = limit;
        this.queue = new LinkedList<>();
    }

    /**
     * 放消息
     */
    public void put(final Message message) throws InterruptedException {
        synchronized (queue){
            if(queue.size()>=limit){
                queue.wait();
            }

            queue.addLast(message);
            queue.notifyAll();
        }
    }

    /**
     * 拿消息
     */
    public Message get() throws InterruptedException {
        synchronized (queue){
            if(queue.isEmpty()){
                queue.wait();
            }

            Message message = queue.removeFirst();
            queue.notifyAll();
            return message;
        }
    }

    /**
     * 獲取最大值
     */
    public int getLimit(){
        return limit;
    }

    /**
     * 獲取當前消息隊列的長度
     */
    public int getQueueSize(){
        synchronized (queue){
            return queue.size();
        }
    }
}

c）生產者

package com.wayne.producerConsumer;

import java.util.Random;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;

public class Producer extends Thread {

    private final MessageQueue queue;

    public final static Random random = new Random(System.currentTimeMillis());

    public final static AtomicInteger counter = new AtomicInteger(0);

    public Producer(MessageQueue queue,int seq){
        super("Producer-"+seq);
        this.queue = queue;
    }

    @Override
    public void run() {
        while (true){
            try {
                Message message = new Message("Message-" + counter.getAndIncrement());
                this.queue.put(message);
                TimeUnit.MILLISECONDS.sleep(random.nextInt(1000));
                System.out.println(currentThread().getName()+"put message:"+message.getData());
            } catch (InterruptedException e) {
                break;
            }
        }
    }
}

d）消費者

package com.wayne.producerConsumer;

import java.util.Random;
import java.util.concurrent.TimeUnit;

public class Consumer extends Thread {
    private final MessageQueue queue;

    private final Random random = new Random(System.currentTimeMillis());

    public Consumer(MessageQueue queue,int seq){
        super("Consumer-"+seq);
        this.queue = queue;
    }

    @Override
    public void run() { 
        while (true){
            try {
                Message message = this.queue.get();
                TimeUnit.MILLISECONDS.sleep(random.nextInt(1000));
                System.out.println(currentThread().getName()+"get message:"+message.getData());
            } catch (InterruptedException e) {
                break;
            }
        }
    }
}

e）測試用例

package com.wayne.producerConsumer;

import java.util.stream.IntStream;

public class ProducerConsumer {

    public static void main(String[] args) {
        MessageQueue messageQueue = new MessageQueue();

        new Producer(messageQueue,1).start();
        new Producer(messageQueue,2).start();
        new Producer(messageQueue,3).start();

        new Consumer(messageQueue,1).start();
        new Consumer(messageQueue,2).start();
    }
}

f）結果輸出