Resettable Java Timer

According to the Timer documentation, in Java 1.5 onwards, you should prefer the ScheduledThreadPoolExecutor instead. (You may like to create this executor using Executors.newSingleThreadScheduledExecutor() for ease of use; it creates something much like a Timer.)

The cool thing is, when you schedule a task (by calling schedule()), it returns a ScheduledFuture object. You can use this to cancel the scheduled task. You’re then free to submit a new task with a different triggering time.

ETA: The Timer documentation linked to doesn’t say anything about ScheduledThreadPoolExecutor, however the OpenJDK version had this to say:

Java 5.0 introduced the java.util.concurrent package and
one of the concurrency utilities therein is the
ScheduledThreadPoolExecutor which is a thread pool for repeatedly
executing tasks at a given rate or delay. It is effectively a more
versatile replacement for the Timer/TimerTask
combination, as it allows multiple service threads, accepts various
time units, and doesn’t require subclassing TimerTask (just
implement Runnable). Configuring
ScheduledThreadPoolExecutor with one thread makes it equivalent to
Timer.

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