private void checkRegexLiteral(PsiElement regex) {
    String[] parts;
    if (regex instanceof GrRegex) {
      parts = ((GrRegex)regex).getTextParts();
    }
    else {
      parts = new String[]{regex.getFirstChild().getNextSibling().getText()};
    }

    for (String part : parts) {
      if (!GrStringUtil.parseRegexCharacters(part, new StringBuilder(part.length()), null, regex.getText().startsWith("/"))) {
        myHolder.newAnnotation(HighlightSeverity.ERROR, GroovyBundle.message("illegal.escape.character.in.string.literal")).range(regex).create();
        return;
      }
    }
  }
private void checkRegexLiteral(PsiElement regex)