Host Name Vs Canonical Host Name

There are a few difference between the two:

• getCanonicalHostName() will attempt to resolve the FQDN. Therefore, you would get foo.mycompany.com whereas getHostName() might just return foo.

• getCanonicalHostName() will always do a reverse DNS lookup, whereas getHostName() would return the stored hostname if you supplied one in the InetAddress constructor.

I suspect you will be wanting to use getCanonicalHostName() if you are intending to map IP addresses to host names.