ip和long互转

/**
 * ClassName: Ip2Long<br/>
 * Description: ip和long互转<br/>
 * date: 2019/4/16 5:53 PM<br/>
 *
 * @author chengluchao
 * @since JDK 1.8
 */

public class Ip2Long {
    public static void main(String[] args) {
        System.out.println(ipToLong("78.23.0.142"));
        System.out.println(longToIP(ipToLong("1.2.3.4")));
    }


    public static long ipToLong(String ip) {
        ip = ip.replaceAll(" ", "");
        String[] ipArray = ip.split("\.");
        long ipLong = (Long.parseLong(ipArray[0]) << 24)
                + (Long.parseLong(ipArray[1]) << 16)
                + (Long.parseLong(ipArray[2]) << 8)
                + Long.parseLong(ipArray[3]);
        return ipLong;
    }

    public static String longToIP(long ip) {
        long a = ip % 256;
        long b = (ip -= a) >> 24;
        long c = (ip -= b << 24) >> 16;
        long d = (ip -= c << 16) >> 8;
        StringBuffer sb = new StringBuffer();
        sb.append(b);
        sb.append(".");
        sb.append(c);
        sb.append(".");
        sb.append(d);
        sb.append(".");
        sb.append(a);
        return sb.toString();
    }
}