I am trying to implement security features for an android app and have tracked down a problem coming from populateHostAddresses() in AbstractXMPPConnection.
It appears the issue is the specific constructor this function uses for HostAddress(port, HostAddress). The issue is that this constructor calls the main constructor HostAddress(fqdn, port, List of iNetAddresses) while passing null into the FQDN.
I think this is a bug, and should be changed to use the main constructor so that the FQDN is not always null. Alternatively the HostAddress constructor HostAddress(port, hostAddress) could be changed to attempt to extract an FQDN from the hostAddress and pass that into the main constructor.