|The core thread pool size which is smaller than the maximum pool size. If undefined, the core thread pool size is the same as the maximum thread pool size.
|Used to specify the amount of time that pool threads should be kept running when idle; if not specified, threads will run until the executor is shut down.
|The maximum thread pool size.
|Specifies the name of a specific thread factory to use to create worker threads. If not defined an appropriate default thread factory will be used.