@NotNull
  public CodeStyleScheme findPreferredScheme(@Nullable String preferredSchemeName) {
    CodeStyleScheme scheme = null;
    if (preferredSchemeName != null) {
      scheme = findSchemeByName(preferredSchemeName);
    }
    if (scheme == null) {
      scheme = getCurrentScheme();
    }
    if (scheme == null) {
      scheme = getDefaultScheme();
    }
    return scheme;
  }
@NotNull
  public CodeStyleScheme findPreferredScheme(@Nullable String preferredSchemeName)