code: private static BufferedReader getLibertyTraceListReader(String resourceName) throws FileNotFoundException {
          InputStream traceListStream = TrConfigurator.class.getClassLoader().getResourceAsStream(resourceName);
          if (traceListStream == null) {
              traceListStream = new FileInputStream(resourceName);
          }
          return new BufferedReader(new InputStreamReader(traceListStream));
      }
docs: /*
  Get the reader for the liberty.ras.rawtracelist.properties file.
  Attempt to get resource as stream from the class loader,
  otherwise try to load from file. This will also assist during testing,
  where the resource name can be specified as a file name.