docs: public static void createAndRegister() throws IOException {
      StackdriverTraceExporter.createAndRegister(
          StackdriverTraceConfiguration.builder()
              .setCredentials(GoogleCredentials.getApplicationDefault())
  
              // TODO(sebright): Handle null default project ID.
              .setProjectId(castNonNull(ServiceOptions.getDefaultProjectId()))
              .build());
    }