课堂笔记之自定义线程池

来源：互联网发布：c语言入门经典编辑：程序博客网时间：2024/05/01 03:17

以下文字内容，可能有误，理解不够透彻

线程池在加载任务时

任务先一次加载到线程池中,如果扩容到最大线程数还不够用，就会放入阻塞队列中取等待,如果队列的长度不够放,就会爆出错误

核心线程,是系统会优先使用的,如果优先的不够用才会扩容到够用为止

并且在核心线程第一次开始启动加载任务时，会顺序排队执行，一个完成，下一个才能开始。然后再随机加载甚至扩容

public class ThreadPoolDemo03 {

   private static final ThreadFactory sThreadFactory = new ThreadFactory() {
        private final AtomicInteger mCount = new AtomicInteger(1);

        public Thread newThread(Runnable r) {
            return new Thread(r, "AsyncTask #" + mCount.getAndIncrement());
        }
    };


   public static void main(String[] args) {
       BlockingQueue<Runnable> workQueue = new LinkedBlockingQueue<Runnable>(20);

       Executor pool = new ThreadPoolExecutor(5, 20, 1, TimeUnit.SECONDS,workQueue,sThreadFactory);
//       new ThreadPoolExecutor(corePoolSize, maximumPoolSize, keepAliveTime, unit, workQueue, threadFactory)

       for(int i=0; i<100; i++)
       pool.execute(new Runnable() {

           @Override
           public void run() {
               try {
                   Thread.sleep(1000);
               } catch (InterruptedException e) {
                   // TODO Auto-generated catch block
                   e.printStackTrace();
               }
               String name = Thread.currentThread().getName();
               System.out.println(name+ "--->");
           }
       });


   }
}

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