public static void main(String[] args) {
    final long timeInterval = 5000;
    new Thread(new Runnable() {
        @Override
        public void run() {
            while (true) {
                System.out.println(Thread.currentThread().getName() + "每隔5秒執(zhí)行一次");
                try {
                    Thread.sleep(timeInterval);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
            }
        }
    }).start();
}

public static void main(String[] args) {
    Timer timer = new Timer();
    //每隔1秒調(diào)用一次
    timer.schedule(new TimerTask() {
        @Override
        public void run() {
            System.out.println("test1");
        }
    }, 1000, 1000);
    //每隔3秒調(diào)用一次
    timer.schedule(new TimerTask() {
        @Override
        public void run() {
            System.out.println("test2");
        }
    }, 3000, 3000);

}

public void schedule(TimerTask task, long delay, long period) {
    if (delay < 0)
        throw new IllegalArgumentException("Negative delay.");
    if (period <= 0)
        throw new IllegalArgumentException("Non-positive period.");
    sched(task, System.currentTimeMillis()+delay, -period);
}

private void sched(TimerTask task, long time, long period) {
    if (time < 0)
        throw new IllegalArgumentException("Illegal execution time.");

    // Constrain value of period sufficiently to prevent numeric
    // overflow while still being effectively infinitely large.
    if (Math.abs(period) > (Long.MAX_VALUE >> 1))
        period >>= 1;

    synchronized(queue) {
        if (!thread.newTasksMayBeScheduled)
            throw new IllegalStateException("Timer already cancelled.");

        synchronized(task.lock) {
            if (task.state != TimerTask.VIRGIN)
                throw new IllegalStateException(
                    "Task already scheduled or cancelled");
            task.nextExecutionTime = time;
            task.period = period;
            task.state = TimerTask.SCHEDULED;
        }

        queue.add(task);
        if (queue.getMin() == task)
            queue.notify();
    }
}

public class Timer {
    
    private final TaskQueue queue = new TaskQueue();

    private final TimerThread thread = new TimerThread(queue);

    public Timer() {
        this("Timer-" + serialNumber());
    }

    public Timer(String name) {
        thread.setName(name);
        thread.start();
    }

    //...
}

class TaskQueue {
    
    private TimerTask[] queue = new TimerTask[128];


    private int size = 0;

    void add(TimerTask task) {
        // Grow backing store if necessary
        if (size + 1 == queue.length)
            queue = Arrays.copyOf(queue, 2*queue.length);

        queue[++size] = task;
        fixUp(size);
    }

    private void fixUp(int k) {
        while (k > 1) {
            int j = k >> 1;
            if (queue[j].nextExecutionTime <= queue[k].nextExecutionTime)
                break;
            TimerTask tmp = queue[j];
            queue[j] = queue[k];
            queue[k] = tmp;
            k = j;
        }
    }
    
    //....
}

class TimerThread extends Thread {

    boolean newTasksMayBeScheduled = true;

    private TaskQueue queue;

    TimerThread(TaskQueue queue) {
        this.queue = queue;
    }

    public void run() {
        try {
            mainLoop();
        } finally {
            // Someone killed this Thread, behave as if Timer cancelled
            synchronized(queue) {
                newTasksMayBeScheduled = false;
                queue.clear();  // Eliminate obsolete references
            }
        }
    }

    /**
     * The main timer loop.  (See class comment.)
     */
    private void mainLoop() {
        while (true) {
            try {
                TimerTask task;
                boolean taskFired;
                synchronized(queue) {
                    // Wait for queue to become non-empty
                    while (queue.isEmpty() && newTasksMayBeScheduled)
                        queue.wait();
                    if (queue.isEmpty())
                        break; // Queue is empty and will forever remain; die

                    // Queue nonempty; look at first evt and do the right thing
                    long currentTime, executionTime;
                    task = queue.getMin();
                    synchronized(task.lock) {
                        if (task.state == TimerTask.CANCELLED) {
                            queue.removeMin();
                            continue;  // No action required, poll queue again
                        }
                        currentTime = System.currentTimeMillis();
                        executionTime = task.nextExecutionTime;
                        if (taskFired = (executionTime<=currentTime)) {
                            if (task.period == 0) { // Non-repeating, remove
                                queue.removeMin();
                                task.state = TimerTask.EXECUTED;
                            } else { // Repeating task, reschedule
                                queue.rescheduleMin(
                                  task.period<0 ? currentTime   - task.period
                                                : executionTime + task.period);
                            }
                        }
                    }
                    if (!taskFired) // Task hasn't yet fired; wait
                        queue.wait(executionTime - currentTime);
                }
                if (taskFired)  // Task fired; run it, holding no locks
                    task.run();
            } catch(InterruptedException e) {
            }
        }
    }
}

public static void main(String[] args) {
    ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(3);
    //啟動(dòng)1秒之后，每隔1秒執(zhí)行一次
    executor.scheduleAtFixedRate((new Runnable() {
        @Override
        public void run() {
            System.out.println("test3");
        }
    }),1,1, TimeUnit.SECONDS);
    //啟動(dòng)1秒之后，每隔3秒執(zhí)行一次
    executor.scheduleAtFixedRate((new Runnable() {
        @Override
        public void run() {
            System.out.println("test4");
        }
    }),1,3, TimeUnit.SECONDS);
}

public ScheduledFuture<?> scheduleAtFixedRate(Runnable command,
                                              long initialDelay,
                                              long period,
                                              TimeUnit unit) {
    if (command == null || unit == null)
        throw new NullPointerException();
    if (period <= 0)
        throw new IllegalArgumentException();
    ScheduledFutureTask<Void> sft =
        new ScheduledFutureTask<Void>(command,
                                      null,
                                      triggerTime(initialDelay, unit),
                                      unit.toNanos(period));
    RunnableScheduledFuture<Void> t = decorateTask(command, sft);
    sft.outerTask = t;
    delayedExecute(t);
    return t;
}

private void delayedExecute(RunnableScheduledFuture<?> task) {
    if (isShutdown())
        reject(task);
    else {
        super.getQueue().add(task);
        if (isShutdown() &&
            !canRunInCurrentRunState(task.isPeriodic()) &&
            remove(task))
            task.cancel(false);
        else
            //預(yù)處理
            ensurePrestart();
    }
}

public ScheduledThreadPoolExecutor(int corePoolSize) {
    super(corePoolSize, Integer.MAX_VALUE, 0, NANOSECONDS,
          new DelayedWorkQueue());
}

static class DelayedWorkQueue extends AbstractQueue<Runnable>
        implements BlockingQueue<Runnable> {

    private static final int INITIAL_CAPACITY = 16;
    private RunnableScheduledFuture<?>[] queue =
        new RunnableScheduledFuture<?>[INITIAL_CAPACITY];
    private final ReentrantLock lock = new ReentrantLock();
    private int size = 0;   

    //....

    public boolean add(Runnable e) {
        return offer(e);
    }

    public boolean offer(Runnable x) {
        if (x == null)
            throw new NullPointerException();
        RunnableScheduledFuture<?> e = (RunnableScheduledFuture<?>)x;
        final ReentrantLock lock = this.lock;
        lock.lock();
        try {
            int i = size;
            if (i >= queue.length)
                grow();
            size = i + 1;
            if (i == 0) {
                queue[0] = e;
                setIndex(e, 0);
            } else {
                siftUp(i, e);
            }
            if (queue[0] == e) {
                leader = null;
                available.signal();
            }
        } finally {
            lock.unlock();
        }
        return true;
    }

    public RunnableScheduledFuture<?> take() throws InterruptedException {
        final ReentrantLock lock = this.lock;
        lock.lockInterruptibly();
        try {
            for (;;) {
                RunnableScheduledFuture<?> first = queue[0];
                if (first == null)
                    available.await();
                else {
                    long delay = first.getDelay(NANOSECONDS);
                    if (delay <= 0)
                        return finishPoll(first);
                    first = null; // don't retain ref while waiting
                    if (leader != null)
                        available.await();
                    else {
                        Thread thisThread = Thread.currentThread();
                        leader = thisThread;
                        try {
                            available.awaitNanos(delay);
                        } finally {
                            if (leader == thisThread)
                                leader = null;
                        }
                    }
                }
            }
        } finally {
            if (leader == null && queue[0] != null)
                available.signal();
            lock.unlock();
        }
    }
}

private class ScheduledFutureTask<V>
            extends FutureTask<V> implements RunnableScheduledFuture<V> {

    /** Sequence number to break ties FIFO */
    private final long sequenceNumber;

    /** The time the task is enabled to execute in nanoTime units */
    private long time;

    /**
     * Period in nanoseconds for repeating tasks.  A positive
     * value indicates fixed-rate execution.  A negative value
     * indicates fixed-delay execution.  A value of 0 indicates a
     * non-repeating task.
     */
    private final long period;

    /** The actual task to be re-enqueued by reExecutePeriodic */
    RunnableScheduledFuture<V> outerTask = this;

    /**
     * Overrides FutureTask version so as to reset/requeue if periodic.
     */
    public void run() {
        boolean periodic = isPeriodic();
        if (!canRunInCurrentRunState(periodic))
            cancel(false);
        else if (!periodic)
            ScheduledFutureTask.super.run();
        else if (ScheduledFutureTask.super.runAndReset()) {
            setNextRunTime();
            reExecutePeriodic(outerTask);
        }
    }
    
    //...
}

public class RingBufferWheel {

    private Logger logger = LoggerFactory.getLogger(RingBufferWheel.class);


    /**
     * default ring buffer size
     */
    private static final int STATIC_RING_SIZE = 64;

    private Object[] ringBuffer;

    private int bufferSize;

    /**
     * business thread pool
     */
    private ExecutorService executorService;

    private volatile int size = 0;

    /***
     * task stop sign
     */
    private volatile boolean stop = false;

    /**
     * task start sign
     */
    private volatile AtomicBoolean start = new AtomicBoolean(false);

    /**
     * total tick times
     */
    private AtomicInteger tick = new AtomicInteger();

    private Lock lock = new ReentrantLock();
    private Condition condition = lock.newCondition();

    private AtomicInteger taskId = new AtomicInteger();
    private Map<Integer, Task> taskMap = new ConcurrentHashMap<>(16);

    /**
     * Create a new delay task ring buffer by default size
     *
     * @param executorService the business thread pool
     */
    public RingBufferWheel(ExecutorService executorService) {
        this.executorService = executorService;
        this.bufferSize = STATIC_RING_SIZE;
        this.ringBuffer = new Object[bufferSize];
    }


    /**
     * Create a new delay task ring buffer by custom buffer size
     *
     * @param executorService the business thread pool
     * @param bufferSize      custom buffer size
     */
    public RingBufferWheel(ExecutorService executorService, int bufferSize) {
        this(executorService);

        if (!powerOf2(bufferSize)) {
            throw new RuntimeException("bufferSize=[" + bufferSize + "] must be a power of 2");
        }
        this.bufferSize = bufferSize;
        this.ringBuffer = new Object[bufferSize];
    }

    /**
     * Add a task into the ring buffer(thread safe)
     *
     * @param task business task extends {@link Task}
     */
    public int addTask(Task task) {
        int key = task.getKey();
        int id;

        try {
            lock.lock();
            int index = mod(key, bufferSize);
            task.setIndex(index);
            Set<Task> tasks = get(index);

            int cycleNum = cycleNum(key, bufferSize);
            if (tasks != null) {
                task.setCycleNum(cycleNum);
                tasks.add(task);
            } else {
                task.setIndex(index);
                task.setCycleNum(cycleNum);
                Set<Task> sets = new HashSet<>();
                sets.add(task);
                put(key, sets);
            }
            id = taskId.incrementAndGet();
            task.setTaskId(id);
            taskMap.put(id, task);
            size++;
        } finally {
            lock.unlock();
        }

        start();

        return id;
    }


    /**
     * Cancel task by taskId
     * @param id unique id through {@link #addTask(Task)}
     * @return
     */
    public boolean cancel(int id) {

        boolean flag = false;
        Set<Task> tempTask = new HashSet<>();

        try {
            lock.lock();
            Task task = taskMap.get(id);
            if (task == null) {
                return false;
            }

            Set<Task> tasks = get(task.getIndex());
            for (Task tk : tasks) {
                if (tk.getKey() == task.getKey() && tk.getCycleNum() == task.getCycleNum()) {
                    size--;
                    flag = true;
                    taskMap.remove(id);
                } else {
                    tempTask.add(tk);
                }

            }
            //update origin data
            ringBuffer[task.getIndex()] = tempTask;
        } finally {
            lock.unlock();
        }

        return flag;
    }

    /**
     * Thread safe
     *
     * @return the size of ring buffer
     */
    public int taskSize() {
        return size;
    }

    /**
     * Same with method {@link #taskSize}
     * @return
     */
    public int taskMapSize(){
        return taskMap.size();
    }

    /**
     * Start background thread to consumer wheel timer, it will always run until you call method {@link #stop}
     */
    public void start() {
        if (!start.get()) {

            if (start.compareAndSet(start.get(), true)) {
                logger.info("Delay task is starting");
                Thread job = new Thread(new TriggerJob());
                job.setName("consumer RingBuffer thread");
                job.start();
                start.set(true);
            }

        }
    }

    /**
     * Stop consumer ring buffer thread
     *
     * @param force True will force close consumer thread and discard all pending tasks
     *              otherwise the consumer thread waits for all tasks to completes before closing.
     */
    public void stop(boolean force) {
        if (force) {
            logger.info("Delay task is forced stop");
            stop = true;
            executorService.shutdownNow();
        } else {
            logger.info("Delay task is stopping");
            if (taskSize() > 0) {
                try {
                    lock.lock();
                    condition.await();
                    stop = true;
                } catch (InterruptedException e) {
                    logger.error("InterruptedException", e);
                } finally {
                    lock.unlock();
                }
            }
            executorService.shutdown();
        }


    }


    private Set<Task> get(int index) {
        return (Set<Task>) ringBuffer[index];
    }

    private void put(int key, Set<Task> tasks) {
        int index = mod(key, bufferSize);
        ringBuffer[index] = tasks;
    }

    /**
     * Remove and get task list.
     * @param key
     * @return task list
     */
    private Set<Task> remove(int key) {
        Set<Task> tempTask = new HashSet<>();
        Set<Task> result = new HashSet<>();

        Set<Task> tasks = (Set<Task>) ringBuffer[key];
        if (tasks == null) {
            return result;
        }

        for (Task task : tasks) {
            if (task.getCycleNum() == 0) {
                result.add(task);

                size2Notify();
            } else {
                // decrement 1 cycle number and update origin data
                task.setCycleNum(task.getCycleNum() - 1);
                tempTask.add(task);
            }
            // remove task, and free the memory.
            taskMap.remove(task.getTaskId());
        }

        //update origin data
        ringBuffer[key] = tempTask;

        return result;
    }

    private void size2Notify() {
        try {
            lock.lock();
            size--;
            if (size == 0) {
                condition.signal();
            }
        } finally {
            lock.unlock();
        }
    }

    private boolean powerOf2(int target) {
        if (target < 0) {
            return false;
        }
        int value = target & (target - 1);
        if (value != 0) {
            return false;
        }

        return true;
    }

    private int mod(int target, int mod) {
        // equals target % mod
        target = target + tick.get();
        return target & (mod - 1);
    }

    private int cycleNum(int target, int mod) {
        //equals target/mod
        return target >> Integer.bitCount(mod - 1);
    }

    /**
     * An abstract class used to implement business.
     */
    public abstract static class Task extends Thread {

        private int index;

        private int cycleNum;

        private int key;

        /**
         * The unique ID of the task
         */
        private int taskId ;

        @Override
        public void run() {
        }

        public int getKey() {
            return key;
        }

        /**
         *
         * @param key Delay time(seconds)
         */
        public void setKey(int key) {
            this.key = key;
        }

        public int getCycleNum() {
            return cycleNum;
        }

        private void setCycleNum(int cycleNum) {
            this.cycleNum = cycleNum;
        }

        public int getIndex() {
            return index;
        }

        private void setIndex(int index) {
            this.index = index;
        }

        public int getTaskId() {
            return taskId;
        }

        public void setTaskId(int taskId) {
            this.taskId = taskId;
        }
    }


    private class TriggerJob implements Runnable {

        @Override
        public void run() {
            int index = 0;
            while (!stop) {
                try {
                    Set<Task> tasks = remove(index);
                    for (Task task : tasks) {
                        executorService.submit(task);
                    }

                    if (++index > bufferSize - 1) {
                        index = 0;
                    }

                    //Total tick number of records
                    tick.incrementAndGet();
                    TimeUnit.SECONDS.sleep(1);

                } catch (Exception e) {
                    logger.error("Exception", e);
                }

            }

            logger.info("Delay task has stopped");
        }
    }
}

public static void main(String[] args) {
    RingBufferWheel ringBufferWheel = new RingBufferWheel( Executors.newFixedThreadPool(2));
    for (int i = 0; i < 3; i++) {
        RingBufferWheel.Task job = new Job();
        job.setKey(i);
        ringBufferWheel.addTask(job);
    }
}

public static class Job extends RingBufferWheel.Task{
    @Override
    public void run() {
        System.out.println("test5");
    }
}

test5
test5
test5