1.10. Multithreading the Endpoint Publisher

In the examples so far, the Endpoint publisher has been single-threaded and, therefore, capable of handling only one client request at a time: the published service completes the processing of one request before beginning the processing of another request. If the processing of the current request hangs, then no subsequent request can be processed unless and until the hung request is processed to completion.

In production mode, the Endpoint publisher would need to handle concurrent requests so that several pending requests could be processed at the same time. If the underlying computer system is, for example, a symmetric multiprocessor (SMP), then separate CPUs could process different requests concurrently. On a single-CPU machine, the concurrency would occur through time sharing; that is, each request would get a share of the available CPU cycles so that several requests would be in some stage of processing at any given time. In Java, concurrency is achieved through multithreading. At issue, then, is how to make the Endpoint publisher multithreaded. The JWS framework supports Endpoint multithreading without forcing the programmer to work with difficult, error-prone constructs such as the synchronized block or the wait and notify method invocations.