code: private String getMainPropertyFileName() throws StartupException {
          String configLoc = getConfigLocation();
          File file = new File(configLoc == null ? MDW_PROPERTIES_FILE_NAME : (configLoc+MDW_PROPERTIES_FILE_NAME));
          if (file.exists())
              return MDW_PROPERTIES_FILE_NAME;
          URL url = this.getClass().getClassLoader().getResource(MDW_PROPERTIES_FILE_NAME);
          if (url != null)
              return MDW_PROPERTIES_FILE_NAME;
          return null;
      }
docs: Null means not found.