code: @Override
      public void trace( String message,
                         Object... params ) {
          if (!isTraceEnabled()) return;
          if (message == null) return;
          logger.trace(StringUtil.createString(message, params));
      }
docs: Log a message at the TRACE level according to the specified format and (optional) parameters. The message should contain a
  pair of empty curly braces for each of the parameter, which should be passed in the correct order. This method is efficient
  and avoids superfluous object creation when the logger is disabled for the TRACE level.
  
  @param message the message string
  @param params the parameter values that are to replace the variables in the format string