java正则验证匹配IP地址

public static boolean isIpv4(String ipAddress) {

		String ip = "^(1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|[1-9])\\."
			    +"(00?\\d|1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\."
			    +"(00?\\d|1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)\\."
			    +"(00?\\d|1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)$";

		Pattern pattern = Pattern.compile(ip);
		Matcher matcher = pattern.matcher(ipAddress);
		return matcher.matches();

	}