java并发-BlockingQueue

java.util.concurrent.BlockingQueue 接口有以下阻塞队列的实现

• ArrayBlockingQueue:规定大小的BlockingQueue,其构造函数必须带一个int参数来指明其大小.其所含的对象是以FIFO(先入先出)顺序排序的.
• LinkedBlockingQueue:大小不定的BlockingQueue,若其构造函数带一个规定大小的参数,生成的BlockingQueue有大小限制,若不带大小参数,所生成的BlockingQueue的大小由Integer.MAX_VALUE来决定.其所含的对象是以FIFO(先入先出)顺序排序的
• PriorityBlockingQueue:类似于LinkedBlockQueue,但其所含对象的排序不是FIFO,而是依据对象的自然排序顺序或者是构造函数的Comparator决定的顺序.
• SynchronousQueue:特殊的BlockingQueue,对其的操作必须是放和取交替完成的.

FIFO 队列 ：LinkedBlockingQueue、ArrayListBlockingQueue（固定长度）
优先级队列 ：PriorityBlockingQueue

提供了阻塞的 take() 和 put() 方法：如果队列为空 take() 将阻塞，直到队列中有内容；如果队列为满 put() 将阻塞，指到队列有空闲位置。

package com.br.lucky.utils;

import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;

/**
 * @author 10400
 * @create 2018-04-20 1:52
 */
public class BlockingQueueDemo {

    private static BlockingQueue<String> queue = new ArrayBlockingQueue<>(5);

    private static class Producer extends Thread {
        @Override
        public void run() {
            try {
                Thread.sleep(5000);
                double random = Math.random();
                queue.put(""+random);
                System.out.println("produce :" + random);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    private static class Consumer extends Thread {

        @Override
        public void run() {
            try {
                Thread.sleep(3000);
                String product = queue.take();
                System.out.println("consume :"+product);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    public static void main(String[] args) {
        for (int i = 0; i < 2; i++) {
            Producer producer = new Producer();
            producer.start();
        }
        for (int i = 0; i < 5; i++) {
            Consumer consumer = new Consumer();
            consumer.start();
        }
        for (int i = 0; i < 3; i++) {
            Producer producer = new Producer();
            producer.start();
        }
    }
}