Java Concurrency in Practice

Chapter 7. Cancellation and Shutdown

It is easy to start tasks and threads. Most of the time we allow them to decide when to stop by letting them run to completion. Sometimes, however, we want to stop tasks or threads earlier than they would on their own, perhaps because the user cancelled an operation or the application needs to shut down quickly.

Getting tasks and threads to stop safely, quickly, and reliably is not always easy. Java does not provide any mechanism for safely forcing a thread to stop what it is doing.^[1] Instead, it provides interruption, a cooperative mechanism that lets one thread ask another to stop what it is doing.

[1] The deprecated Thread.stop and suspend methods were an attempt to provide such a mechanism, but were quickly ...