package com.efounder.chat.utils;

import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;


/**
 * 线程池辅助类，整个应用程序就只有一个线程池去管理线程。
 * 可以设置核心线程数、最大线程数、额外线程空状态生存时间，阻塞队列长度来优化线程池。
 * 下面的数据都是参考Android的AsynTask里的数据。
 * @author zet  yqs
 * 这篇文章讲解很细
 * https://blog.csdn.net/qq_25806863/article/details/71126867
 *
 */
public class CommonThreadPoolUtils {

    private CommonThreadPoolUtils(){
        
    }
    
    //线程池核心线程数
    private static int CORE_POOL_SIZE = 10;
    
    //线程池最大线程数
    private static int MAX_POOL_SIZE = 30;
    
    //额外线程空状态生存时间
    private static int KEEP_ALIVE_TIME = 15;
    
    //阻塞队列。当核心线程都被占用，且阻塞队列已满的情况下，才会开启额外线程。
    private static LinkedBlockingQueue<Runnable> workQueue = new LinkedBlockingQueue<Runnable>(
            );
    
    //线程工厂
    private static ThreadFactory threadFactory = new ThreadFactory() {
        private final AtomicInteger integer = new AtomicInteger();

        @Override
        public Thread newThread(Runnable r) {
            return new Thread(r, "myThreadPool thread:" + integer.getAndIncrement());
        }
    };

    //线程池
    private static ThreadPoolExecutor threadPool;
    
    static {
        threadPool = new ThreadPoolExecutor(CORE_POOL_SIZE,
                MAX_POOL_SIZE, KEEP_ALIVE_TIME, TimeUnit.SECONDS, workQueue,
                threadFactory);
    }

    /**
     * 从线程池中抽取线程，执行指定的Runnable对象
     * @param runnable
     */
    public static void execute(Runnable runnable){
        threadPool.execute(runnable);
    }

}