Get the server port number from tomcat without a request

Question

Is there any Tomcat API or configuration available which can tell an application (probably on startup), what port its running on without a request?

Imagine a scenari

Answer 1

Previously on a large distributed project, the design I used was to have the centralised service initialise the several services with the central service's URL(& port).

Obviously this means that the central service must maintain a list of the services (URL & port) to initialise.