class LuceneIndexExporter {

  private static final String FIELD_NAME = "fieldLowercase";

  public static void main(String[] args) throws IOException {<FILL_FUNCTION_BODY>}
}

    if (args.length != 1) {
      System.out.println("Usage: " + LuceneIndexExporter.class.getSimpleName() + " <luceneIndexDir>");
      System.exit(1);
    }
    System.out.println("Using field: " + FIELD_NAME);
    Directory directory = SimpleFSDirectory.open(Paths.get(args[0]));
    try (DirectoryReader indexReader = DirectoryReader.open(directory)) {
      for (int i = 0; i < indexReader.maxDoc(); i++) {
        Document doc = indexReader.document(i);
        System.out.println(doc.get(FIELD_NAME));
      }
    }
  
<no_super_class>