线程池原理

  public ThreadPoolExecutor(int corePoolSize,
      int maximumPoolSize,
      long keepAliveTime,
      TimeUnit unit,
      BlockingQueue<Runnable> workQueue,
      ThreadFactory threadFactory,
      RejectedExecutionHandler handler) {
    if (corePoolSize < 0 ||
    maximumPoolSize <= 0 ||
    maximumPoolSize < corePoolSize ||
    keepAliveTime < 0)
    throw new IllegalArgumentException();
    if (workQueue == null || threadFactory == null || handler == null)
    throw new NullPointerException();
    this.acc = System.getSecurityManager() == null ?
    null :
    AccessController.getContext();
    this.corePoolSize = corePoolSize;
    this.maximumPoolSize = maximumPoolSize;
    this.workQueue = workQueue;
    this.keepAliveTime = unit.toNanos(keepAliveTime);
    this.threadFactory = threadFactory;
    this.handler = handler;
    }

corePoolSize 核心线程数；
maximumPoolSize 最大线程数；
keepAliveTime 空闲线程数存活时间；
TimeUnit  时间格式；
BlockingQueue 工作阻塞队列；
threadFactory 线程工厂；
RejectedExecutionHandler 拒绝策略。

来源：https://www.cnblogs.com/SimonHu1993/p/11411332.html