正则表达式验证ip合法性

String regex = "^(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|[1-9])\\."
			+ "(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\." + "(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\."
			+ "(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)$";
if(str.matches(regex )){
	ip合法
}