Why can't it create a 'will' parameter, like creating ‘auth’, giving a null value if it is not appropriate?

[aruis]

These two pieces of code should explain the problem

vertx-mqtt/src/main/java/io/vertx/mqtt/impl/MqttServerConnection.java

Lines 199 to 204 in c8213e0

	MqttWill will =
	new MqttWill(msg.variableHeader().isWillFlag(),
	msg.payload().willTopic(),
	msg.payload().willMessage(),
	msg.variableHeader().willQos(),
	msg.variableHeader().isWillRetain());

vertx-mqtt/src/main/java/io/vertx/mqtt/impl/MqttServerConnection.java

Lines 207 to 211 in c8213e0

	MqttAuth auth = (msg.variableHeader().hasUserName() &&
	msg.variableHeader().hasPassword()) ?
	new MqttAuth(
	msg.payload().userName(),
	msg.payload().password()) : null;

Because of this problem, this code makes no sense.

https://github.com/vert-x3/vertx-examples/blob/5cec6110ae68ef587c66e00eaba89c4adf285d09/mqtt-examples/src/main/java/io/vertx/example/mqtt/app/Server.java#L53