java中如何使用URL检测地址是否存在呢？

实现思路:
    使用HttpURLConnection检测访问URL
	 是否返回HTTP_OK 
	 当返回200,则代表URL地址存在

public static boolean urlExists(String URLName){
    try {
      HttpURLConnection.setFollowRedirects(false); 

      HttpURLConnection con =
         (HttpURLConnection) new URL(URLName).openConnection();
          con.setRequestMethod("HEAD");
      return (con.getResponseCode() == HttpURLConnection.HTTP_OK);
    }
    catch (Exception e) {
       e.printStackTrace();
       return false;
    }
  }