问题
I was using HiveMQ Client version 1.0.1 but I decided to update to the recently released version 1.1. I completely started from scratch and imported the project as a Gradle project and tried to build. The build work only after ignoring a few failed tests. I'm getting 3 errors in 3 different classes. I realize this is likely related to the Dagger dependency injection tool and I had already successfully built the project and added the directory of build/generated/source/apt/main/ to my build path as noted by my previous stack post where I had issues with a DaggerSingletonComponent not being found: How to fix DaggerSingletonComponent not resolved in HiveMQ (MQTT protocol) . This seems to be a new issue and I'm not sure what's wrong. I tried rebuilding by project but the errors still persist. I've left some screenshot below as well as the specific errors.
HiveMQ:
https://github.com/hivemq/hivemq-community-edition
https://github.com/hivemq/hivemq-mqtt-client
Errors:
The constructor MqttChannelInitializer(MqttClientConfig, MqttConnAckFlow, MqttEncoder, MqttConnectHandler, MqttDisconnectHandler, MqttAuthHandler, Lazy) is undefined
The constructor MqttSession(MqttClientConfig, MqttSubscriptionHandler, MqttIncomingQosHandler, MqttOutgoingQosHandler) is undefined
The method provideBootstrap(NettyEventLoopProvider, MqttChannelInitializer) in the type ConnectionModule is not applicable for the arguments (MqttClientConfig, NettyEventLoopProvider, MqttChannelInitializer)
Screenshots:
回答1:
Executing ./gradlew clean build on the command line will fix your error.
But I also think that the real solution for your use case is to create a new empty project (gradle or maven) and add the client library as a dependency, like described here: https://hivemq.github.io/hivemq-mqtt-client/docs/installation.html
回答2:
The issue turned out to be caused by an issue with the source folder in the directory build/generated/source/apt/main/ not having the option “Update exclusion filters in other source folders to solve nesting” selected. Selecting that option solved all of the errors.
来源：https://stackoverflow.com/questions/56588395/how-to-fix-undefined-mqttchannelinitializer-constructor-in-hivemq-client