concurrency - Why is there no scheduled cached thread pool provided by the Java Executors class?

Question

Executors provides newCachedThreadPool() and newScheduledThreadPool(), but not newCachedScheduledThreadPool(), what gives here? I have an application that receives bursty messages and needs to schedule a fairly lengthy processing step after a fixed delay for each. The time constraints aren't super tight, but I would prefer to have more threads created on the fly if I exceed the pool size and then have them trimmed back during periods of inactivity. Is there something I've missed in the concurrent library, or do I need to write my own?

question from:https://stackoverflow.com/questions/3281269/why-is-there-no-scheduled-cached-thread-pool-provided-by-the-java-executors-clas

Answer 1

By design the ScheduledThreadPoolExecutor is a fixed size. You can use a single threaded version that submits to a normal ExecutorService for performing the task. This event thread + worker pool is fairly ease to coordinate and the flexibility makes up for the dedicated thread. I've used this in the past to replace TimerTasks and other non-critical tasks to utilize a common executor as a system-wide pool.