10.java Excutor框架

固定线程池 newFixedThreadPool 缓存线程池 newCachedThreadPool 单个线程 newSingleThreadExecutor 定时线程池 newScheduledThreadPool

    //固定线程池
    public static ExecutorService newFixedThreadPool(int nThreads) {
        return new ThreadPoolExecutor( nThreads, nThreads,
                0L, TimeUnit.MILLISECONDS,
                new LinkedBlockingQueue<Runnable>() );
    }

    //缓存线程池
    public static ExecutorService newCachedThreadPool() {
        return new ThreadPoolExecutor( 0, Integer.MAX_VALUE,
                60L, TimeUnit.SECONDS,
                new SynchronousQueue<Runnable>() );
    }


    //单个线程池
    public static ExecutorService newSingleThreadExecutor() {
        return new ThreadPoolExecutor( 1, 1,
                0L, TimeUnit.MILLISECONDS,
                new LinkedBlockingQueue<Runnable>() );
    }

    //定时线程池
    public static ExecutorService newScheduledThreadPoolExecutor(int corePoolSize) {
        return new ThreadPoolExecutor( corePoolSize, Integer.MAX_VALUE, 0, NANOSECONDS,
                new ScheduledThreadPoolExecutor.DelayedWorkQueue() );
    }

 int cpu = Runtime.getRuntime().availableProcessors();

CPU密集型：Ncpu+1
IO密集型：2* Ncpu