shutdown

Blocks new tasks and waits up to a specified period of time for all tasks to be completed. If that time expires, the execution is stopped immediately. Any tasks that did not start execution will have their corresponding item's status set to PENDING. Shutdown is idempotent, so multiple invocations will have no additional effect. Note that if the library is used in Spring, you may notice two invocations of shutdown, one from the @PreDestroy and one via the automatic inference as described here.