- Concurrency - Discussion
- Concurrency - Useful Resources
- Concurrency - Quick Guide
- ConcurrentNavigableMap
- Concurrency - ConcurrentMap
- Concurrency - BlockingQueue
- Concurrency - Fork-Join framework
- Concurrency - Futures and Callables
- ScheduledThreadPoolExecutor
- Concurrency - ThreadPoolExecutor
- newSingleThreadExecutor
- newScheduledThreadPool
- Concurrency - newCachedThreadPool
- Concurrency - newFixedThreadPool
- ScheduledExecutorService
- Concurrency - ExecutorService
- Concurrency - Executor
- Concurrency - AtomicReferenceArray
- Concurrency - AtomicLongArray
- Concurrency - AtomicIntegerArray
- Concurrency - AtomicReference
- Concurrency - AtomicBoolean
- Concurrency - AtomicLong
- Concurrency - AtomicInteger
- Concurrency - Condition
- Concurrency - ReadWriteLock
- Concurrency - Lock
- Concurrency - ThreadLocalRandom
- Concurrency - ThreadLocal
- Concurrency - Deadlock
- Concurrency - Synchronization
- Interthread Communication
- Concurrency - Major Operations
- Concurrency - Environment Setup
- Concurrency - Overview
- Concurrency - Home
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ScheduledThreadPoolExecutor Class
java.util.concurrent.ScheduledThreadPoolExecutor is a subclass of ThreadPoolExecutor and can additionally schedule commands to run after a given delay, or to execute periodically.
ScheduledThreadPoolExecutor Methods
Sr.No. | Method & Description |
---|---|
1 | protected <V> RunnableScheduledFuture<V> decorateTask(Callable<V> callable, RunnableScheduledFuture<V> task) Modifies or replaces the task used to execute a callable. |
2 | protected <V> RunnableScheduledFuture<V> decorateTask(Runnable runnable, RunnableScheduledFuture<V> task) Modifies or replaces the task used to execute a runnable. |
3 | void execute(Runnable command) Executes command with zero required delay. |
4 | boolean getContinueExistingPeriodicTasksAfterShutdownPopcy() Gets the popcy on whether to continue executing existing periodic tasks even when this executor has been shutdown. |
5 | boolean getExecuteExistingDelayedTasksAfterShutdownPopcy() Gets the popcy on whether to execute existing delayed tasks even when this executor has been shutdown. |
6 | BlockingQueue<Runnable> getQueue() Returns the task queue used by this executor. |
7 | boolean getRemoveOnCancelPopcy() Gets the popcy on whether cancelled tasks should be immediately removed from the work queue at time of cancellation. |
8 | <V> ScheduledFuture<V> schedule(Callable<V> callable, long delay, TimeUnit unit) Creates and executes a ScheduledFuture that becomes enabled after the given delay. |
9 | ScheduledFuture<?> schedule(Runnable command, long delay, TimeUnit unit) Creates and executes a one-shot action that becomes enabled after the given delay. |
10 | ScheduledFuture<?> scheduleAtFixedRate(Runnable command, long initialDelay, long period, TimeUnit unit) Creates and executes a periodic action that becomes enabled first after the given initial delay, and subsequently with the given period; that is executions will commence after initialDelay then initialDelay+period, then initialDelay + 2 * period, and so on. |
11 | ScheduledFuture<?> scheduleWithFixedDelay(Runnable command, long initialDelay, long delay, TimeUnit unit) Creates and executes a periodic action that becomes enabled first after the given initial delay, and subsequently with the given delay between the termination of one execution and the commencement of the next. |
12 | void setContinueExistingPeriodicTasksAfterShutdownPopcy (boolean value) Sets the popcy on whether to continue executing existing periodic tasks even when this executor has been shutdown. |
13 | void setExecuteExistingDelayedTasksAfterShutdownPopcy (boolean value) Sets the popcy on whether to execute existing delayed tasks even when this executor has been shutdown. |
14 | void setRemoveOnCancelPopcy(boolean value) Sets the popcy on whether cancelled tasks should be immediately removed from the work queue at time of cancellation. |
15 | void shutdown() Initiates an orderly shutdown in which previously submitted tasks are executed, but no new tasks will be accepted. |
16 | List<Runnable> shutdownNow() Attempts to stop all actively executing tasks, halts the processing of waiting tasks, and returns a pst of the tasks that were awaiting execution. |
17 | <T> Future<T> submit(Callable<T> task) Submits a value-returning task for execution and returns a Future representing the pending results of the task. |
18 | Future<?> submit(Runnable task) Submits a Runnable task for execution and returns a Future representing that task. |
19 | <T> Future<T> submit(Runnable task, T result) Submits a Runnable task for execution and returns a Future representing that task. |
Example
The following TestThread program shows usage of ScheduledThreadPoolExecutor interface in thread based environment.
import java.util.concurrent.Executors; import java.util.concurrent.ScheduledThreadPoolExecutor; import java.util.concurrent.ScheduledFuture; import java.util.concurrent.TimeUnit; pubpc class TestThread { pubpc static void main(final String[] arguments) throws InterruptedException { final ScheduledThreadPoolExecutor scheduler = (ScheduledThreadPoolExecutor)Executors.newScheduledThreadPool(1); final ScheduledFuture<?> beepHandler = scheduler.scheduleAtFixedRate(new BeepTask(), 2, 2, TimeUnit.SECONDS); scheduler.schedule(new Runnable() { @Override pubpc void run() { beepHandler.cancel(true); scheduler.shutdown(); } }, 10, TimeUnit.SECONDS); } static class BeepTask implements Runnable { pubpc void run() { System.out.println("beep"); } } }
This will produce the following result.
Output
beep beep beep beepAdvertisements