code: Object getAsyncDeliveryLock() {
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.entry(this, tc, "getAsyncDeliveryLock");
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              SibTr.exit(this, tc, "getAsyncDeliveryLock", asyncDeliveryLock);
          return asyncDeliveryLock;
      }
docs: Returns the asyncDeliveryLock for this Session.