Executors - 969251639/study GitHub Wiki

public class Executors {
    ...
    //生成固定大小的线程池，其中核心线程数和最大线程数都是一样的，阻塞队列用LinkedBlockingQueue，几乎无限大，有OOM风险
    public static ExecutorService newFixedThreadPool(int nThreads, ThreadFactory threadFactory) {
        return new ThreadPoolExecutor(nThreads, nThreads,
                                      0L, TimeUnit.MILLISECONDS,
                                      new LinkedBlockingQueue<Runnable>(),
                                      threadFactory);
    }

    //生成只有一个线程的线程池，其中核心线程数和最大线程数都是1，阻塞队列用LinkedBlockingQueue，几乎无限大，有OOM风险
    public static ExecutorService newSingleThreadExecutor() {
        return new FinalizableDelegatedExecutorService
            (new ThreadPoolExecutor(1, 1,
                                    0L, TimeUnit.MILLISECONDS,
                                    new LinkedBlockingQueue<Runnable>()));
    }
    public static ExecutorService newSingleThreadExecutor(ThreadFactory threadFactory) {
        return new FinalizableDelegatedExecutorService
            (new ThreadPoolExecutor(1, 1,
                                    0L, TimeUnit.MILLISECONDS,
                                    new LinkedBlockingQueue<Runnable>(),
                                    threadFactory));
    }

    //生成可动态伸缩的线程池，其中核心线程数是0，最大线程数都是int的最大值（2147483647），阻塞队列用SynchronousQueue，线程池几乎可以无限扩大，SynchronousQueue并不缓存任务，线程数可以在0和2147483647直接动态伸缩，有OOM风险，一般不用
    public static ExecutorService newCachedThreadPool() {
        return new ThreadPoolExecutor(0, Integer.MAX_VALUE,
                                      60L, TimeUnit.SECONDS,
                                      new SynchronousQueue<Runnable>());
    }
    public static ExecutorService newCachedThreadPool(ThreadFactory threadFactory) {
        return new ThreadPoolExecutor(0, Integer.MAX_VALUE,
                                      60L, TimeUnit.SECONDS,
                                      new SynchronousQueue<Runnable>(),
                                      threadFactory);
    }
    ...
}