Java APIs

On some machines, domains starting with the hyphen (and other non-alphabetic characters) are not resolved by InetAddress.getByName()
nslookup does resolve the domains, so they seem to be valid - perhaps not by the RFC, but it seems that other common tools do consider the domain to be valid.

here are some domains that fail:

----thomiiii.hi5.com
*.letsgodigital.es
*.chordie.com

I found the org.xbill.DNS package that resolves these domains.

Wondering why the InetAddress class does not. I tried looking at the source, but it led me to a native implemention:

static native InetAddress getHostByNameImpl(String name, boolean preferIPv6Address) throws UnknownHostException;

but i couldn't find the source for this native implementation.

Here is a bit of code that runs the two functions together. After it hits the exception with the InetAddress function, it retries with the Address function (from the org.xbill.DNS package, which works)

import java.net.InetAddress;
import org.xbill.DNS.Address;

public class MemLimitCheck {
    public static void main(String[] args) {

        try {
            InetAddress ia = InetAddress.getByName(args[0]);
            byte[] addr = ia.getAddress();
            String host = ia.getHostAddress();
            System.out.println(host);
        } catch (Exception e){
            System.err.println(e.getMessage());
            e.printStackTrace();

            try {
                InetAddress ia = Address.getByName(args[0]);
                byte[] addr = ia.getAddress();
                String host = ia.getHostAddress();
                System.out.println(host);                
            } catch (Exception t) {
                System.err.println(t.getMessage());
                t.printStackTrace();
            }

        }

    }
}

Edited by: thushw on Jul 20, 2010 11:40 AM

Edited by: thushw on Jul 20, 2010 11:40 AM

Edited by: thushw on Jul 20, 2010 11:41 AM

Edited by: thushw on Jul 20, 2010 11:42 AM