判断IP地址是否合法

if (StringUtils.isNotEmpty(address.getIp())) {
            if (address.getIp().length()<7||address.getIp().length()>15){
                String msg = "请输入合法的IP地址!";
                return AjaxResult.error(msg);
            }else {
                if ( IpAddress.isIP(dkyIpconfSdzzIp.getYwipdz())) {
                    String dz = address.getIp();
                    String[] sdzz = dz.split("\\.");
                    int ip1 = Integer.valueOf(sdzz[0]);
                    int ip2 = Integer.valueOf(sdzz[1]);
                    int ip3 = Integer.valueOf(sdzz[2]);
                    int ip4 = Integer.valueOf(sdzz[3]);
                    if ((ip1 < 0 || ip1 > 255) || (ip2 < 0 || ip2 > 255) || (ip3 < 0 || ip3 > 255) || (ip4 < 0 || ip4 > 255)) {
                        String msg = "您输入正常范围内的IP地址!";
                        return AjaxResult.error(msg);
                    }
                }else {
                    String msg = "IP地址不正确!";
                    return AjaxResult.error(msg);
                }
            }
        }

IpAddress类

public class IpAddress {
    public static boolean isIP(String addr) {
        if (addr==null || addr.length() < 7 || addr.length() > 15 || "".equals(addr)) {
            return false;
        }
        /**
         * 判断IP格式和范围
         */
        String rexp =
                "([1-9]|[1-9]\\d|1\\d{2}|2[0-4]\\d|25[0-5])(\\.(\\d|[1-9]\\d|1\\d{2}|2[0-4]\\d|25[0-5])){3}";

        Pattern pat = Pattern.compile(rexp);

        Matcher mat = pat.matcher(addr);

        boolean ipAddress = mat.find();

        return ipAddress;
    }
}