The default local address is often just "the first address found in the list of addresses read from the OS" and this might mean an internal IP address that cannot reach external servers. So wherever possible use the same IP address being used to connect to the XMPP server because this local address has a better chance of being suitable.
This MR adds the above behaviour, and two UTs to test that we use the local XMPP connection IP when connected, and the previous behaviour when not.
This also resulted in a refactoring of the Providers and parsing
Exceptions. NumberFormatException and ParseException can now be thrown
directly, the wrapping in a SmackParsingException is down at a higher
layer, i.e. in AbstractProvider.
This also removes the powermock dependency. Although powermock is a
fine library, it currently prevents dropping Junit4. And since we only
use the Whitebox API of powermock, this simply replaced powermock's
Whitebox with our own.
Martin Fidczuk
Florian Schmaus