This post shows the code required to convert an IPv4 Address to Number and vice versa.
The below-mentioned lines convert an IPv4 Address to Long.
// IP
String ip = "192.168.1.1";
// IP Octets string array
String[] octets = ip.split( "\\." );
// IP Octets integer array
int[] octetsNum = new int[] {
Integer.parseInt( octets[ 0 ] ),
Integer.parseInt( octets[ 1 ] ),
Integer.parseInt( octets[ 2 ] ),
Integer.parseInt( octets[ 3 ] )
};
// IP in numeric form
long ipNum = ( octetsNum[ 0 ] * (int)Math.pow( 256, 3 ) ) + ( octetsNum[ 1 ] * (int)Math.pow( 256, 2 ) ) + ( octetsNum[ 2 ] * 256 ) + ( octetsNum[ 3 ] );
We can also convert the number back to IPv4 Address as shown below.
// IP in numeric form
long ipNum = -1062731519;
// Convert numeric IP to IPv4 Address
String ipAddr = ( ( ipNum >> 24 ) & 0xFF ) + "." + ( ( ipNum >> 16 ) & 0xFF ) + "." + ( ( ipNum >> 8 ) & 0xFF ) + "." + ( ipNum & 0xFF );
Below mentioned is the complete and tested code.
package networking;
public class IpUtil {
public static void main( String args[] ) {
// Stores the IP Address
String ipOctets = "192.168.1.1";
IpUtil ipUtil = new IpUtil();
// Convert IP to Number
long ipNum = ipUtil.ipToNum( ipOctets );
// Print the number
System.out.println( "The number of given IP Address : " + ipOctets + " is: " + ipNum );
// Convert Number back to IP
ipOctets = ipUtil.numToIp( ipNum );
// Print the IP
System.out.println( "The IP Address of given number : " + ipNum + " is: " + ipOctets );
}
/**
* Convert and return the given IP Octets to number.
*/
public long ipToNum( String ip ) {
long ipNum = -1;
// IP Octets string array
String[] octets = ip.split( "\\." );
// IP Octets integer array
int[] octetsNum = new int[] {
Integer.parseInt( octets[ 0 ] ),
Integer.parseInt( octets[ 1 ] ),
Integer.parseInt( octets[ 2 ] ),
Integer.parseInt( octets[ 3 ] )
};
// IP in numeric form
ipNum = ( octetsNum[ 0 ] * (int)Math.pow( 256, 3 ) ) + ( octetsNum[ 1 ] * (int)Math.pow( 256, 2 ) ) + ( octetsNum[ 2 ] * 256 ) + ( octetsNum[ 3 ] );
return ipNum;
}
public String numToIp( long ipNum ) {
// Convert numeric IP to IPv4 Address
String ipAddr = ( ( ipNum >> 24 ) & 0xFF ) + "." + ( ( ipNum >> 16 ) & 0xFF ) + "." + ( ( ipNum >> 8 ) & 0xFF ) + "." + ( ipNum & 0xFF );
return ipAddr;
}
}
The output should be the same as mentioned below.
The number of given IP Address : 192.168.1.1 is: -1062731519
The IP Address of given number : -1062731519 is: 192.168.1.1
