@ElementTypesAreNonnullByDefault
public enum CaseFormat {
  /** Hyphenated variable naming convention, e.g., "lower-hyphen". */
  LOWER_HYPHEN(CharMatcher.is('-'), "-") {
    @Override
    String normalizeWord(String word) {
      return Ascii.toLowerCase(word);
    }

    @Override
    String convert(CaseFormat format, String s) {
      if (format == LOWER_UNDERSCORE) {
        return s.replace('-', '_');
      }

@ElementTypesAreNonnullByDefault
public enum CaseFormat {
  /** Hyphenated variable naming convention, e.g., "lower-hyphen". */
  LOWER_HYPHEN(CharMatcher.is('-'), "-") {
    @Override
    String normalizeWord(String word) {
      return Ascii.toLowerCase(word);
    }

    @Override
    String convert(CaseFormat format, String s) {
      if (format == LOWER_UNDERSCORE) {
        return s.replace('-', '_');
      }