让用户输入带或不带括号的电话号码的区号。

import java.util.regex.Matcher;
/*
N o w J a v a . c o m - 时代Java 提 供
*/

import java.util.regex.Pattern;


public class Main {

  public static void main(String[] args) {

    Pattern pattern = Pattern.compile("((\\d{3} )|(\\(\\d{3}\\) ))?\\d{3}-\\d{4}");

    Matcher matcher = pattern.matcher("559 555-1234");

    if (matcher.matches())

      System.out.println("Match.");

    else

      System.out.println("Does not match.");

  }


}