docs: @Override
      public void debug( Throwable t,
                         String message,
                         Object... params ) {
          if (!isDebugEnabled()) return;
          if (t == null) {
              debug(message, params);
              return;
          }
          if (message == null) {
              logger.debug(null, t);
              return;
          }
          logger.debug(StringUtil.createString(message, params), t);
      }