How to have all webmethod calls of a webservice be handled by the same function? (JAX-WS)

Question

The idea is to have a client calling different webmethods but at the server side having all the calls redirected to one entry point where authentication/permissions are checked and then let the call continue. This is:

client side                       server side
------------                      --------------
                                       (proxy)                 del (delegate)
serv.foo(token, arg) --------->   entry_point:
                                   if ok(token)
                                    del.foo(arg) -----------> actual foo() implem.

serv.bar(token,arg1,arg2) ---->   entry_point:
                                   if ok(token)
                                    del.bar(arg1,arg2)  ----> actual bar() implem.

I have clear that the proxy is to be coded using reflection. The problem is how to redirect calls from client side to the proxy entry point. I've tried Dynamic proxy

• in the server side: problem: the WS doesn't expose the interface methods (foo() bar()) to the client (the object to be published is the one returned by Proxy.newProxyInstance() and it doesn't have them)

• in the client side: bar() and token() calls are redirected to the dynamic proxy invoke() method (great !). Then I try to forward the call to a WS with invoke() as the only webmethod (and same paramaters than the original method), BUT: problem: the WS can't hold the invoke parameters:

  public Object invoke(Object proxy, Method method, Object[] args) throws Throwable

  (it complains about the Method argument).

Any suggestion, or different approach?