executor 正确停止方法.md

private static final AtomicInteger FACTORY_ID = new AtomicInteger();

private final ScheduledExecutorService executor = Executors.newSingleThreadScheduledExecutor(new NamedThreadFactory(name + '-' + FACTORY_ID.incrementAndGet()));

public void stop() {
    executor.shutdown(); // Disable new tasks from being submitted
    try {
        // Wait a while for existing tasks to terminate
        if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {
            executor.shutdownNow(); // Cancel currently executing tasks
            // Wait a while for tasks to respond to being cancelled
            if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {
                System.err.println(getClass().getSimpleName() + ": ScheduledExecutorService did not terminate");
            }
        }
    } catch (InterruptedException ie) {
        // (Re-)Cancel if current thread also interrupted
        executor.shutdownNow();
        // Preserve interrupt status
        Thread.currentThread().interrupt();
    }
}


private static class NamedThreadFactory implements ThreadFactory {
    private final ThreadGroup group;
    private final AtomicInteger threadNumber = new AtomicInteger(1);
    private final String namePrefix;

    private NamedThreadFactory(String name) {
        final SecurityManager s = System.getSecurityManager();
        this.group = (s != null) ? s.getThreadGroup() : Thread.currentThread().getThreadGroup();
        this.namePrefix = "metrics-" + name + "-thread-";
    }

    @Override
    public Thread newThread(Runnable r) {
        final Thread t = new Thread(group, r, namePrefix + threadNumber.getAndIncrement(), 0);
        t.setDaemon(true);
        if (t.getPriority() != Thread.NORM_PRIORITY) {
            t.setPriority(Thread.NORM_PRIORITY);
        }
        return t;
    }
}