private void
openConnection() throws IOException {
	long endTime = System.currentTimeMillis() + timeout;
	client = new TCPClient(endTime);
	if (localAddress != null)
		client.bind(localAddress);
	client.connect(address);
}
Sets the local address to bind to when sending messages.
@param addr The local address to send messages from.
src/main/java/core/org/xbill/DNS/ZoneTransferIn.java