Android中ThreadPoolExecutor线程池shutDownNow() 无法中断

public List<Runnable> shutdownNow() {List<Runnable> tasks;final ReentrantLock mainLock = this.mainLock;mainLock.lock();try {checkShutdownAccess();advanceRunState(STOP);interruptWorkers();tasks = drainQueue();} finally {mainLock.unlock();}tryTerminate();return tasks;}

shutdownNow 是interrupt所有线程， 因此大部分线程将立刻被中断。之所以是大部分，而不是全部 ，是因为interrupt()方法能力有限。

如果线程中没有sleep 、wait、Condition、定时锁等应用, interrupt()方法是无法中断当前的线程的。所以，ShutdownNow()并不代表线程池就一定立即就能退出，它可能必须要等待所有正在执行的任务都执行完成了才能退出。

long t1 = System.currentTimeMillis();ExecutorService singleThread = newSingleThreadExecutor().execute(() -> {try {while (true) {long t2 = System.currentTimeMillis();if ((t2 - t1 > timeout * 1000) && timeout > 0) {//timeoutbreak;}// do somethingThread.sleep(10);}} catch (InterruptedException e) {e.printStackTrace();}new MaterialDialog.Builder(this).content(\"waiting...\").contentGravity(GravityEnum.CENTER).cancelListener((dialog) -> {singleThread.shutdownNow();dialog.dismiss();}).show();