Check whether the IP is in private range

개발하다보면 현재 IP가 공인 IP인지 사설 IP인지 구분해야할 때가 있다.

 

import java.net.InetAddress;
import java.net.UnknownHostException;

public class LocalAddress {

    public static void main(String[] args) {
        InetAddress address = null;
        
        try {
            address = InetAddress.getLocalHost();
        } catch (UnknownHostException e) {
             e.printStackTrace();
        }
        
        if (address.isSiteLocalAddress()) {
            System.out.println("Site Local Address: " + address.getHostAddress());
        } else {
            System.out.println("Routeable Address: " + address.getHostAddress());
        }
    }

}

위와 같이 사용 가능하다. 또는

 

import com.google.common.net.InetAddresses;

private static boolean isPrivateV4Address(String ip) {
    int address = InetAddresses.coerceToInteger(InetAddresses.forString(ip));
    return (((address >>> 24) & 0xFF) == 10)
            || ((((address >>> 24) & 0xFF) == 172) 
              && ((address >>> 16) & 0xFF) >= 16 
              && ((address >>> 16) & 0xFF) <= 31)
            || ((((address >>> 24) & 0xFF) == 192) 
              && (((address >>> 16) & 0xFF) == 168));
}

직접 API를 정의해서 사용할 수도 있다.

 

출처 :

https://stackoverflow.com/questions/9729378/check-whether-the-ipaddress-is-in-private-range/9729432

Check whether the ipAddress is in private range