How do I close ScheduledExecutorService?
ScheduledExecutorService Shutdown You shut down a ScheduledExecutorService using the shutdown() or shutdownNow() methods which are inherited from the ExecutorService interface.
How do you stop a Java scheduler?
The cancel() method is used to cancel the timer task. The cancel() methods returns true when the task is scheduled for one-time execution and has not executed until now and returns false when the task was scheduled for one-time execution and has been executed already.
What is ScheduledThreadPoolExecutor?
ScheduledThreadPoolExecutor class in Java is a subclass of ThreadPoolExecutor class defined in java. util. As it is clear from its name that this class is useful when we want to schedule tasks to run repeatedly or to run after a given delay for some future time. It creates a fixed-sized Thread Pool.
What is ScheduledFuture?
Interface ScheduledFuture A delayed result-bearing action that can be cancelled. Usually a scheduled future is the result of scheduling a task with a ScheduledExecutorService . Since: 1.5.
How do you terminate an executor?
The ExecutorService class has 2 methods just for this: shutdown() and shutdownNow(). After using the shutdown() method, you can call awaitTermination() to block until all of the started tasks have completed. You can even provide a timeout to prevent waiting forever.
How do you terminate an executor in Java?
To properly shut down an ExecutorService, we have the shutdown() and shutdownNow() APIs. The shutdown() method doesn’t cause immediate destruction of the ExecutorService. It will make the ExecutorService stop accepting new tasks and shut down after all running threads finish their current work: executorService.
What is TimerTask cancel?
Java TimerTask cancel() Method This method is used to stop the timer task if the task is scheduled for 1-time execution or has not been run. It will never run again if the task has been scheduled for repeated execution.
How do I shut down ScheduledThreadPoolExecutor?
When you want to stop the scheduler you must do something like this: //Cancel scheduled but not started task, and avoid new ones myScheduler. shutdown(); //Wait for the running tasks myScheduler. awaitTermination(30, TimeUnit.
What is scheduleAtFixedRate?
Description. The scheduleAtFixedRate(TimerTask task,long delay,long period) method is used to schedule the specified task for repeated fixed-rate execution, beginning after the specified delay.
How do I use ScheduledFuture?
Java ScheduledExecutorService examples
- Run a Task Once. The ScheduledExecutorService accepts both Runnable and Callable tasks. 1.1 Run a Runnable task after 5 seconds initial delay.
- Run a Task Periodically. To run a task periodically, uses scheduleAtFixedRate.
When can an executor service be shut down?
An ExecutorService should be shut down once it is no longer needed to free up system resources and to allow graceful application shutdown. Because the threads in an ExecutorService may be nondaemon threads, they may prevent normal application termination.