The schedule methods create tasks with various delays and return a task object that can be used to cancel or check execution. The scheduleAtFixedRate and scheduleWithFixedDelay methods create and execute tasks that run periodically until cancelled.
Commands submitted using the {@link Executor#execute} and{@link ExecutorService} submit methods are scheduled witha requested delay of zero. Zero and negative delays (but not periods) are also allowed in schedule methods, and are treated as requests for immediate execution.
All schedule methods accept relative delays and periods as arguments, not absolute times or dates. It is a simple matter to transform an absolute time represented as a {@link edu.emory.mathcs.backport.java.util.Date} to the required form. For example, to schedule ata certain future date, you can use: schedule(task, date.getTime() - System.currentTimeMillis(), TimeUnit.MILLISECONDS). Beware however that expiration of a relative delay need not coincide with the current Date at which the task is enabled due to network time synchronization protocols, clock drift, or other factors. The {@link Executors} class provides convenient factory methods forthe ScheduledExecutorService implementations provided in this package.
import static edu.emory.mathcs.backport.java.util.concurrent.TimeUnit.*; class BeeperControl { private final ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(1); public void beepForAnHour() { final Runnable beeper = new Runnable() { public void run() { System.out.println("beep"); } }; final ScheduledFuture<?> beeperHandle = scheduler.scheduleAtFixedRate(beeper, 10, 10, SECONDS); scheduler.schedule(new Runnable() { public void run() { beeperHandle.cancel(true); } }, 60 * 60, SECONDS); } }
@since 1.5
@author Doug Lea
The {@code schedule} methods create tasks with various delaysand return a task object that can be used to cancel or check execution. The {@code scheduleAtFixedRate} and{@code scheduleWithFixedDelay} methods create and execute tasksthat run periodically until cancelled.
Commands submitted using the {@link Executor#execute(Runnable)}and {@link ExecutorService} {@code submit} methods are scheduledwith a requested delay of zero. Zero and negative delays (but not periods) are also allowed in {@code schedule} methods, and aretreated as requests for immediate execution.
All {@code schedule} methods accept relative delays andperiods as arguments, not absolute times or dates. It is a simple matter to transform an absolute time represented as a {@link java.util.Date} to the required form. For example, to schedule ata certain future {@code date}, you can use: {@code schedule(task,date.getTime() - System.currentTimeMillis(), TimeUnit.MILLISECONDS)}. Beware however that expiration of a relative delay need not coincide with the current {@code Date} atwhich the task is enabled due to network time synchronization protocols, clock drift, or other factors.
The {@link Executors} class provides convenient factory methods forthe ScheduledExecutorService implementations provided in this package.
{@code import static java.util.concurrent.TimeUnit.*;}class BeeperControl private final ScheduledExecutorService scheduler = Executors.newScheduledThreadPool(1); public void beepForAnHour() { final Runnable beeper = new Runnable() { public void run() { System.out.println("beep"); } }; final ScheduledFuture beeperHandle = scheduler.scheduleAtFixedRate(beeper, 10, 10, SECONDS); scheduler.schedule(new Runnable() { public void run() { beeperHandle.cancel(true); } }, 60 * 60, SECONDS); } }}
@since 1.5
@author Doug Lea
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