code: public void warning(
              String sourceClass,
              String sourceMethod,
              String msg
              )
      {
          logp(Level.WARNING, sourceClass, sourceMethod, msg);
      }
docs: Log a WARNING message, with no arguments.
  <p>
  The message is forwarded to appropriate Java Logger objects.
  <p>
  @param sourceClass  the name of the class that issued the logging request
  @param sourceMethod the name of the method that issued the logging request
  @param msg          the string message (or a key in the resource bundle)