java多线程生产多线程消费模式模式

应用场景

比如我们需要上传一个excel 需要多线程校验，校验通过后直接插入数据库，这个时候我们就可以使用多线程校验 校验通过后多线程插入数据库场景，类似场景有非常多 文件上传 文件下载 文件生成 只要能用到多线程的地方都能适用上 要学会举一反三 不一一举例，废话不多说 直接上代码

代码模拟多线程生产任务 多线程同时消费的场景

运行结果示例

代码

package com.hyun.test.my;

import java.util.Random;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.Callable;
import java.util.concurrent.CompletionService;
import java.util.concurrent.ExecutorCompletionService;
import java.util.concurrent.Future;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

/**
 * 多线程生产-消费模式
 * @author hyun
 *
 */
public class Test {
	/**
	 * 生产任务线程 需自定义
	 * @author hyun
	 *
	 */
	static class Producer implements Callable<String> {
		//生产任务需要的参数
		private final int paramData;
		
		public Producer(int paramData)  {
			this.paramData = paramData;
		}
		@Override
		public String call() throws Exception {
			//模拟实际操作 随机睡眠10m内
			Random random = new Random();
			Thread.sleep(random.nextInt(10) * 1000);
			System.out.println("paramData-" + paramData + " has producer");
			return "paramData-" + paramData ;
		}
		
	}
	/**
	 * 消费任务 需自定义
	 * @author hyun
	 *
	 */
	static class Consume implements Callable<String> {
		//消费任务需要的参数
		private final String consumeData;
		
		public Consume(String consumeData)  {
			this.consumeData = consumeData;
		}

		@Override
		public String call() {
			//模拟实际消费任务 输出结果
			System.out.println(consumeData + " has consume");
			return "sucess-" + consumeData;
		}
		
	}

	public static void main(String[] args) throws Exception {
		//线程保持时间(超出线程核心数线程保持时间)
		int keepAliveTime = 5;
		//cpu核心数
		int processors = Runtime.getRuntime().availableProcessors();
		//队列长度 根据实际需要设置
		BlockingQueue<Runnable> producterQueue = new ArrayBlockingQueue<>(5000);
		//生产队列 如果是io操作 processors*2  否则processors+1
		ThreadPoolExecutor producterThreadPool = new ThreadPoolExecutor(processors * 2, processors * 2, keepAliveTime, TimeUnit.SECONDS, producterQueue);
		CompletionService<String> producterCompletion = new ExecutorCompletionService<>(producterThreadPool);
		
		//任务数量
		int taskSize = 4;
		for(int i = 0; i < taskSize; i++) {
			producterCompletion.submit(new Producer(i));
		}
		
		//队列长度 根据实际需要设置
		BlockingQueue<Runnable> consumeQueue = new ArrayBlockingQueue<>(5000);
		//消费队列 如果是io操作 processors*2  否则processors+1
		ThreadPoolExecutor consumeThreadPool = new ThreadPoolExecutor(processors * 2, processors * 2, keepAliveTime, TimeUnit.SECONDS, consumeQueue);
		CompletionService<String> consumeCompletion = new ExecutorCompletionService<>(producterThreadPool);
		
		//从生产队列producterCompletion获取结果扔入消费队列consumeCompletion 根据先生产完成先消费原则
		for(int i = 0; i < taskSize; i++) {
			Future<String> future = producterCompletion.take();
			String consumeData = future.get();
			consumeCompletion.submit(new Consume(consumeData));
		}
		
		//如果需要取得消费者返回结果 否则不需要
		for(int i = 0; i < taskSize; i++) {
			Future<String> future = consumeCompletion.take();
			String result = future.get();
			//根据返回结果做相关操作
			//System.out.println(result);
		}
		
		
	}
	
}