public Checker tryCreate(String pattern) {
      if (pattern.matches("(\\\\d|\\\\\\(|\\\\\\)|-| )+")) {
        return new PhoneNumberChecker(pattern.replaceAll("\\\\d", "d").replaceAll("\\\\\\(", "(").replaceAll("\\\\\\)", ")"));
      }
      return null;
    }
Accepts phone number REGEXP patterns like "\(\d\d\d\) \d\d\d-\d\d\d\d" and creates
corresponding checkers.
ql/src/java/org/apache/hadoop/hive/ql/exec/vector/expressions/FilterStringColRegExpStringScalar.java