线程池以及四种常见线程池

public ThreadPoolExecutor(int corePoolSize,//核心线程池大小，核心线程将会尽可能地一直活着                          int maximumPoolSize,//线程池最大数量包括核心线程数量                          long keepAliveTime,//非核心线程最长存活时间                          TimeUnit unit,//keepAliveTime的单位                          BlockingQueue
    
      workQueue,//等待线程的队列                          ThreadFactory threadFactory,//线程工程                          RejectedExecutionHandler handler)//线程拒绝执行回调复制代码
    

四种常见的线程池：

• Executors.newCachedThreadPool()

  new ThreadPoolExecutor(0, Integer.MAX_VALUE,                                  60L, TimeUnit.SECONDS,                                  new SynchronousQueue
        
         ())复制代码
        

• Executors.newFixedThreadPool(int nThreads)

  new ThreadPoolExecutor(nThreads, nThreads,                                  0L, TimeUnit.MILLISECONDS,                                  new LinkedBlockingQueue
        
         ())复制代码
        

• Executors.newScheduledThreadPool(int nCorepoolSize)

  public static ScheduledExecutorService newScheduledThreadPool(int corePoolSize) {    return new ScheduledThreadPoolExecutor(corePoolSize);}//ScheduledThreadPoolExecutor():public ScheduledThreadPoolExecutor(int corePoolSize) {    super(corePoolSize, Integer.MAX_VALUE,          DEFAULT_KEEPALIVE_MILLIS, MILLISECONDS,          new DelayedWorkQueue());}复制代码

  ​

• Executors.newSingleThreadPool()

  public static ExecutorService newSingleThreadExecutor() {    return new FinalizableDelegatedExecutorService        (new ThreadPoolExecutor(1, 1,                                0L, TimeUnit.MILLISECONDS,                                new LinkedBlockingQueue
        
         ()));}复制代码
        

  ​