### Question:
UdpConnectionMap { public static void addConnection(InetSocketAddress address, MessageConsumer consumer) { if(address == null){ throw new IllegalArgumentException("Address can not be null"); } connectionMap.put(address, consumer); } private  UdpConnectionMap(); static MessageConsumer getMessageConsumer(InetSocketAddress address); static void addConnection(InetSocketAddress address, MessageConsumer consumer); static void removeConnection(InetSocketAddress address);  }### Answer:
@Test(expected = IllegalArgumentException.class) public void testWithoutSenderAddressOnAdd(){ UdpConnectionMap.addConnection(null, consumerMock); }