code: protected static String quoteRegex(String regex) {
  		if (regex == null) {
  			return ""; //$NON-NLS-1$
  		}
  		return regex.replaceAll(REGEX_SPECIAL_CHARS, REGEX_SPECIAL_CHARS_PROTECT);
  	}
docs: Protect the given regular expression.
  
  @param regex the expression to protect.
  @return the protected expression.