I have an interface that I\'ve exposed as a regular SOAP web service. One method of the interface consists for the client to send a file to the server, then the server processes
If you use some tool like WSDL2Java for client generation, you can even choose to generate an asynchronous client. It will generate for you a callback handler with empty methods for each of the service operations and exceptions of the service. You then can just implement those methods to set the actions to do when the response is received. Remember that when an asynchronous call is done a new thread is started.