code: public ContentSummary getContentSummary(final Path f,
                                            final boolean useStandby)
      throws IOException {
      return new StandbyCaller<ContentSummary>() {
        @Override
        ContentSummary call(DistributedFileSystem fs) throws IOException {
          return fs.getContentSummary(f);
        }
      }.callFS(useStandby);
    }
docs: {@inheritDoc}