How to get IP address of any host without using the built in library function InetAddress.getbyName()?

Question

I am making my own Iterative DNSresolver, where I need the ip of the host to use... but Datagrampacket requires InetAddresstype object. So I had to use the library function.

InetAddress ipAddress = InetAddress.getByName(DNSAddress);
....
//some code
....
DatagramPacket dnsReqPacket = new DatagramPacket(dnsFrame, dnsFrame.length,             ip, DNSServerPort);
....
//some code

So, I was thinking is it possible to make my own getbyName() function without using the inetAddress library?

Answer 1

You can use java.net.InetAddress.getByAddress(byte[]) . It creates an InetAddress object from the raw (network) representation of the address.

The method is rather confusingly named because unlike gethostbyaddr , it does not perform a reverse lookup:

This method doesn't block, ie no reverse name service lookup is performed.

Using an InetAddress created using getByAddress together with DatagramPacket or DatagramSocket does not necessarily trigger name resolution, either, so there is no risk of infinite recursion (in case the Java implementation attempts to perform name resolution using your own DNS implementation).