docs: @Trivial
      public T getOldProvider() {
          if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled()) {
              Tr.debug(tc, "getOldProvider : provider=" + (provider==null?"null":provider.getClass()) + 
                              " oldProvider=" + (oldProvider==null?"null":oldProvider.getClass()));
          }
          return (oldProvider == null) ? provider : oldProvider;
      }