Interface Current

The portable interceptor Current (PICurrent) contains multiple slots where an interceptor can rememeber the request - specific values between subsequent calls of the interceptor methods. In multithreaded environment, it is not possible just to store such data in the interceptor object fields.

On the client side, it is possible to set the initial slot values by modifying slots on the Current, returend by ORB.resolve_initial_references ("PICurrent"). The returned value is narrowed with the {@link CurrentHelper#narrow}. On the subsequent invocation, made from the same thread, the interceptors will see the initial slot values as they were set using this approach.

There are no way to set the initial values for the server side interceptors, the default values (Any with typecode TCKind.tk_null) should be always assumed.

Since an Interceptor is running in a thread, it is running with a thread context and there is a PICurrent on that context. If the Interceptor calls ORB.resolve_initial_references ("PICurrent"), it gets the PICurrent within its thread scope. This PICurrent is different than the request scope PICurrent that the Interceptor obtains via calls to the Client- or Server- RequestInfo object.

On the client side the PICurrent can be used to detect the recursive invocations, performed by interceptors. If one of the interceptors makes call via the same ORB, this call is then showed to all interceptors, including the interceptor that made it. To avoid infinite recursion, the during each call this interceptor can set some "recursion flag" into one of the slots of the PICurrent. If the flag is set on the entry point, this indicates a recursive call of that request.