Appender parseAppender()

in src/main/java/org/apache/log4j/extras/DOMConfigurator.java [217:279]
52 lines of code
10 McCabe index (conditional complexity)

  Appender parseAppender (Element appenderElement) {
    String className = subst(appenderElement.getAttribute(CLASS_ATTR));
    LogLog.debug("Class name: [" + className+']');    
    try {
      Object instance 	= Loader.loadClass(className).newInstance();
      Appender appender	= (Appender)instance;
      PropertySetter propSetter = new PropertySetter(appender);

      appender.setName(subst(appenderElement.getAttribute(NAME_ATTR)));
      
      NodeList children	= appenderElement.getChildNodes();
      final int length 	= children.getLength();

      for (int loop = 0; loop < length; loop++) {
	Node currentNode = children.item(loop);

	/* We're only interested in Elements */
	if (currentNode.getNodeType() == Node.ELEMENT_NODE) {
	  Element currentElement = (Element)currentNode;

	  // Parse appender parameters 
	  if (currentElement.getTagName().equals(PARAM_TAG)) {
            setParameter(currentElement, propSetter);
	  }
	  // Set appender layout
	  else if (currentElement.getTagName().equals(LAYOUT_TAG)) {
	    appender.setLayout(parseLayout(currentElement));
	  }
	  // Add filters
	  else if (currentElement.getTagName().equals(FILTER_TAG)) {
	    parseFilters(currentElement, appender);
	  }
	  else if (currentElement.getTagName().equals(ERROR_HANDLER_TAG)) {
	    parseErrorHandler(currentElement, appender);
	  }
	  else if (currentElement.getTagName().equals(APPENDER_REF_TAG)) {
	    String refName = subst(currentElement.getAttribute(REF_ATTR));
	    if(appender instanceof AppenderAttachable) {
	      AppenderAttachable aa = (AppenderAttachable) appender;
	      LogLog.debug("Attaching appender named ["+ refName+
			   "] to appender named ["+ appender.getName()+"].");
	      aa.addAppender(findAppenderByReference(currentElement));
	    } else {
	      LogLog.error("Requesting attachment of appender named ["+
			   refName+ "] to appender named ["+ appender.getName()+
                "] which does not implement org.apache.log4j.spi.AppenderAttachable.");
	    }
	  } else {
          parseUnrecognizedElement(instance, currentElement, props);
      }
	}
      }
      propSetter.activate();
      return appender;
    }
    /* Yes, it's ugly.  But all of these exceptions point to the same
       problem: we can't create an Appender */
    catch (Exception oops) {
      LogLog.error("Could not create an Appender. Reported error follows.",
		   oops);
      return null;
    }
  }