@Override
  public boolean getAllPossibleValues(List<Completion> completions, Class<?> targetType,
      String existingData, String optionContext, MethodTarget target) {
    completions.add(new Completion("range"));
    completions.add(new Completion("key"));
    completions.add(new Completion("hash"));
    return true;
  }
Added converter to enable auto-completion for index-type
geode-gfsh/src/main/java/org/apache/geode/management/internal/cli/converters/IndexTypeConverter.java