public Object getValue()

in src/main/java/org/apache/log4j/spi/LoggingEventFieldResolver.java [208:261]
50 lines of code
23 McCabe index (conditional complexity)

  public Object getValue(final String fieldName,
                         final LoggingEvent event) {
    String upperField = fieldName.toUpperCase(Locale.US);
    if (LOGGER_FIELD.equals(upperField)) {
      return event.getLoggerName();
    } else if (LEVEL_FIELD.equals(upperField)) {
      return event.getLevel();
    } else if (MSG_FIELD.equals(upperField)) {
      return event.getMessage();
    } else if (NDC_FIELD.equals(upperField)) {
      String ndcValue = event.getNDC();
      return ((ndcValue == null) ? EMPTY_STRING : ndcValue);
    } else if (EXCEPTION_FIELD.equals(upperField)) {
        String[] throwableRep = event.getThrowableStrRep();
        if (throwableRep == null) {
            return EMPTY_STRING;
        } else {
            return getExceptionMessage(throwableRep);
        }
    } else if (TIMESTAMP_FIELD.equals(upperField)) {
      return new Long(event.timeStamp);
    } else if (THREAD_FIELD.equals(upperField)) {
      return event.getThreadName();
    } else if (upperField.startsWith(PROP_FIELD)) {
      //note: need to use actual fieldname since case matters
      Object propValue = event.getMDC(fieldName.substring(5));
      if (propValue == null) {
          //case-specific match didn't work, try case insensitive match
          String lowerPropKey = fieldName.substring(5).toLowerCase();
          Set entrySet = event.getProperties().entrySet();
          for (Iterator iter = entrySet.iterator();iter.hasNext();) {
              Map.Entry thisEntry = (Map.Entry) iter.next();
              if (thisEntry.getKey().toString().equalsIgnoreCase(lowerPropKey)) {
                  propValue = thisEntry.getValue();
              }
          }
      }
      return ((propValue == null) ? EMPTY_STRING : propValue.toString());
    } else {
        LocationInfo info = event.getLocationInformation();
        if (CLASS_FIELD.equals(upperField)) {
            return ((info == null) ? EMPTY_STRING : info.getClassName());
        } else if (FILE_FIELD.equals(upperField)) {
            return ((info == null) ? EMPTY_STRING : info.getFileName());
        } else if (LINE_FIELD.equals(upperField)) {
            return ((info == null) ? EMPTY_STRING : info.getLineNumber());
        } else if (METHOD_FIELD.equals(upperField)) {
            return ((info == null) ? EMPTY_STRING : info.getMethodName());
        }
    }

    //there wasn't a match, so throw a runtime exception
    throw new IllegalArgumentException("Unsupported field name: " + fieldName);
  }