// 智能并发调度控制器：设置[最大并发数]，和[等待队列]大小
SmartExecutor smallExecutor = new SmartExecutor();

// set temporary parameter just for test
// 一下参数设置仅用来测试，具体设置看实际情况。

// number of concurrent threads at the same time, recommended core size is CPU count
// 开发者均衡性能和业务场景，自己调整同一时段的最大并发数量
smallExecutor.setCoreSize(2);

// adjust maximum number of waiting queue size by yourself or based on phone performance
// 开发者均衡性能和业务场景，自己调整最大排队线程数量
smallExecutor.setQueueSize(2);

// 任务数量超出[最大并发数]后，自动进入[等待队列]，等待当前执行任务完成后按策略进入执行状态：后进先执行。
smallExecutor.setSchedulePolicy(SchedulePolicy.LastInFirstRun);

// 后续添加新任务数量超出[等待队列]大小时，执行过载策略：抛弃队列内最旧任务。
smallExecutor.setOverloadPolicy(OverloadPolicy.DiscardOldTaskInQueue);

// 一次投入 4 个任务
for (int i = 0; i < 4; i++) {
    final int j = i;
    smallExecutor.execute(new Runnable() {
        @Override
        public void run() {
            HttpLog.i(TAG, " TASK " + j + " is running now ----------->");
            SystemClock.sleep(j * 200);
        }
    });
}

// 再投入1个可能需要取消的任务
Future future = smallExecutor.submit(new Runnable() {
    @Override
    public void run() {
        HttpLog.i(TAG, " TASK 4 will be canceled... ------------>");
        SystemClock.sleep(1000);
    }
});

// 合适的时机取消此任务
future.cancel(false);

TASK 0 is running now ----------->
TASK 1 is running now ----------->
TASK 3 is running now ----------->

public Future<?> submit(Runnable task)

public <T> Future<T> submit(Runnable task, T result)

public <T> Future<T> submit(Callable<T> task)

public <T> void submit(RunnableFuture<T> task)

public void execute(final Runnable command)

@Override
public void execute(final Runnable command) {
    if (command == null) {
        return;
    }

    WrappedRunnable scheduler = new WrappedRunnable() {
        @Override
        public Runnable getRealRunnable() {
            return command;
        }

        public Runnable realRunnable;

        @Override
        public void run() {
            try {
                command.run();
            } finally {
                scheduleNext(this);
            }
        }
    };

    boolean callerRun = false;
    synchronized (lock) {
        if (runningList.size() < coreSize) {
            runningList.add(scheduler);
            threadPool.execute(scheduler);
        } else if (waitingList.size() < queueSize) {
            waitingList.addLast(scheduler);
        } else {
            switch (overloadPolicy) {
                case DiscardNewTaskInQueue:
                    waitingList.pollLast();
                    waitingList.addLast(scheduler);
                    break;
                case DiscardOldTaskInQueue:
                    waitingList.pollFirst();
                    waitingList.addLast(scheduler);
                    break;
                case CallerRuns:
                    callerRun = true;
                    break;
                case DiscardCurrentTask:
                    break;
                case ThrowExecption:
                    throw new RuntimeException("Task rejected from lite smart executor. " + command.toString());
                default:
                    break;
            }
        }
        //printThreadPoolInfo();
    }
    if (callerRun) {
        command.run();
    }
}