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How to fix undefined MqttChannelInitializer constructor in HiveMQ Client?

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:

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

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.

Unable to derive module descriptor: Provider {class X} not in module

I am getting this error message when I try to compile my new modularized Java 11 application:
Error occurred during initialization of boot layer
java.lang.module.FindException: Unable to derive module descriptor for C:\Users\inter\.m2\repository\xalan\xalan\2.7.2\xalan-2.7.2.jar
Caused by: java.lang.module.InvalidModuleDescriptorException: Provider class org.apache.bsf.BSFManager not in module
This appears to be an issue from a dependency of a dependency. I can't even find which module is pulling it in so I can update it.
I am using openjdk 11.0.2, IntelliJ 2018.3.4, Maven
Any advice how I can troubleshoot or fix this? I have found very little documentation on this issue.

Xalan
I had a look at their bug tracker following their index page and wasn't able to find this reported and not sure how actively is the library being maintained either.
General Explanation
Just to explain what has caused the issue in your code, I would share a screenshot and then try to add details around it.
So within the JAR that for version 2.7.2, there are service declarations (META-INF/services) which include org.apache.xalan.extensions.bsf.BSFManager as one of them. The service file here has to indicate the Provider thereby for itself and the class is supposed to be present on the modulepath to be resolved for reliable configuration of modules.
In this case for the module xalan(automatic module), the service listed doesn't have the provider class packaged within the dependency itself. (See the package org.apache, it doesn't further have package bsf and the class BSFManager thereby. Hence the exception as you get.
Short term hack
One of the tweaks to get that resolved would be to get update the library jar (patch it) and get rid of the service file if you're not using it. Or to add the provider copied from the corresponding artifact.
If you don't directly depend on this artifact or its parent dependencies, you can let those remain on the --classpath and get resolved as an unnamed module for your application.
Long term solve
An ideal way would be to report this to the maintainers and getting it resolved. It depends though on how actively are they maintaining it e.g. the last release for xalan was almost 5 years back, might just want to look for an actively participated alternative in my opinion.

I tried to install update for TestNG in eclipse:
"Help -> Check for updates -> deselect all and select TestNG check box. Then
install latest version i installed the version which starts with 7.2.0.
It fixed the issue for me.

Adding spock to eclipse without maven: General error during semantic analysis

I am trying to do my first test-automation with Spock.
I do not want to use maven.
I am using eclipse java EE oxygen 4.7.
I have created a groovy project.
I have added the Spock jar as an external library in the build path configuration.
Spock ist Spock-core-1.1-groovy-2.4.
I have also added geb jar the same way.
However, I am getting this strange error from the automatic build, which I do not understand and I am seeking for help. So far I haven't found anything helpfull.
General error during semantic analysis: Transform org.spockframework.compiler.SpockTransform#xxxx cannot be run org.codehaus.groovy.GroovyException:
Transform org.spockframework.compiler.SpockTransform#xxxx cannot be run at
org.codehaus.groovy.transform.ASTTransformationVisitor$3.call(ASTTransformationVisitor.java:416) at
org.codehaus.groovy.control.CompilationUnit.applyToSourceUnits(CompilationUnit.java:972) at
org.codehaus.groovy.control.CompilationUnit.doPhaseOperation(CompilationUnit.java:633) at
org.codehaus.groovy.control.CompilationUnit.processPhaseOperations(CompilationUnit.java:609) at
org.codehaus.groovy.control.CompilationUnit.compile(CompilationUnit.java:586) at
org.codehaus.jdt.groovy.internal.compiler.ast.GroovyCompilationUnitDeclaration.processToPhase(GroovyCompilationUnitDeclaration.java:217) at
org.codehaus.jdt.groovy.internal.compiler.ast.GroovyCompilationUnitDeclaration.resolve(GroovyCompilationUnitDeclaration.java:613) at
org.eclipse.jdt.internal.compiler.Compiler.process(Compiler.java:879) at org.eclipse.jdt.internal.compiler.ProcessTaskManager.run(ProcessTaskManager.java:141) at
java.lang.Thread.run(Unknown Source) Caused by: java.lang.NoClassDefFoundError: Unable to load class org.spockframework.runtime.ErrorCollector due to
missing dependency org/junit/runners/model/MultipleFailureException at org.codehaus.groovy.vmplugin.v5.Java5.configureClassNode(Java5.java:397) at
org.codehaus.groovy.ast.ClassNode.lazyClassInit(ClassNode.java:353) at org.codehaus.groovy.ast.ClassNode.getDeclaredMethods(ClassNode.java:981) at
org.codehaus.groovy.ast.ImmutableClassNode.getDeclaredMethods(ImmutableClassNode.java:105) at
org.spockframework.compiler.AstNodeCache.(AstNodeCache.java:65) at org.spockframework.compiler.SpockTransform$Impl.(SpockTransform.java:
52) at org.spockframework.compiler.SpockTransform.visit(SpockTransform.java:47) at
org.codehaus.groovy.transform.ASTTransformationVisitor$3.call(ASTTransformationVisitor.java:395) ... 9 more
My code is as simple as you can get. This is the code:
//The error is on the "p" letter of package
package hellowworld
class HelloWorld{
static main(args) {
}
}
Please note that this error only happens when I add Spock jar. The closest question was Spock without maven or gradle, but obviously the problems are different.

I just cut the file from the package directory pasted it out side and then recut pasted in the package back. It worked well and I have no idea why.

This is one of those problems which occasionally arise in Eclipse and most people just won't know why!
The thing to do usually is to try several "strategies" and hope that one will work. If not you have to come back to SO and try to enlist the support of an expert.
One tip: in my experience sometimes it is worth trying "Refresh Gradle" and "Build all" more than once. Not only that, but sometimes trying either of these actually then seems to do nothing... but a couple of seconds later the horrid x in the red box then vanishes like morning mist!
Highlight/select the project in Project Explorer --> right-click --> Gradle --> Refresh Gradle Project
Put cursor in a code file open in the editor, press Ctrl-B (Project --> Build all)
Close all files in editor, close Eclipse and start up Eclipse again
Try the above in various combinations
Reboot and then try the above in various combinations
If this fails to cure it you may need to turn to SO.

Incompatible Class Change Error: jaxrs-0.7 vs mail-1.0.1

I have a dependency resolution issue with another plugin, which is causing the following error:
Caused by: java.lang.IncompatibleClassChangeError
at grails.plugin.mail.MailMessageContentRenderer$RenderEnvironment.init(MailMessageContentRenderer.groovy:125)
at grails.plugin.mail.MailMessageContentRenderer$RenderEnvironment.with(MailMessageContentRenderer.groovy:158)
at grails.plugin.mail.MailMessageContentRenderer.render(MailMessageContentRenderer.groovy:47)
at grails.plugin.mail.MailMessageBuilder.doRender(MailMessageBuilder.groovy:235)
at grails.plugin.mail.MailMessageBuilder.html(MailMessageBuilder.groovy:253)
The way to recreate the error:
Install jaxrs 0.7 plugin and its dependencies in build config: spock 0.7 and org.springframework:spring-test:3.1.2.RELEASE
When I do run-app, since everything is loaded directly from resources, there is no error. However, doing a run-war, as dependencies are resolved I get the the above error.
The mail plugin depends on org.springframework:spring-test:3.1.0.RELEASE which gets kicked out. So, probably that is the reason.
Any suggestions on how to deal with this issue? I don't necessarily want to recompile the plugin separately as it becomes hard to maintain. I already tried a lot of combination in buildconfig for exclusion, but doesn't seem to work.
Thanks.

compile error: The import xxxx cannot be resolved

I am developing a Java project using Eclipse. The project uses another project called engine, which I have added in my project build-path. As I need to call a dabo class, called House, in one of my project class, named Window, I have used the following code as usual:
import ee.asus.kernel.House;
I got however the following error in compiling time:
Exception in thread "main" java.lang.Error: Unresolved compilation problems:
The import ee cannot be resolved
House cannot be resolved to a type
House cannot be resolved to a type
House cannot be resolved to a type
at main.ee.asus.GUI.FrameWindow.Window.<init>(Window.java:10)
at main.ee.asus.GUI.StartApplication.main(StartApplication.java:13)
It's worth to point out that my prject and the dabo project use the same directory/packages names. Does anyone have a clue where the error may be?

The error can't resolve the first part of the package name: ee. Are you sure the package starts with ee? I see your Window class package starts with main.ee, does your engine project start with the same package structure?

I sometimes get weird behaviour with missing class files etc. when Eclipse is out of sync with the filesystem.
You could try refreshing all of your projects and doing a full rebuild.

I have been experiencing the same problem. I have an app A1(tablet version app) calling another app A2(phone version app). Upon calling, I see the same error message:
java.lang.Error: Unresolved compilation problems:
The import xxxxx cannot be resolved
xxxx cannot be resolved to a type
xxxx cannot be resolved to a type
xxxx cannot be resolved to a type
After poking around for a while, I realized the problem was the A2 doesn't run on tablet at all. It's weird because the immediate previous version of A2 runs perfectly on the same tablet(I have been on board only for 1 month). So I decided there was something wrong in the build config.
Finally, I fixed the problem by changing the order of Java Build Path. Although I have no idea why it worked, hopefully this will shed some light on your problem.

Look for the House class in your second project, opens it and see what package it is in.
(line "package xxx.yyy.zzz;" at the beginning of the House.java file)
Then make sure your Window.java file (class main.ee.asus.GUI.FrameWindow.Window) does have the line "import xxx.yyy.zzz.House;" in it.

In my case it was a version conflict.
I'm using maven and updated many packages and bumped versions of many projects. Maybe the reactor built mixed something up, or the transitive dependencies weren't up-to-date, or it was a change in a project without a version increment. However, rebuilding that project explicitly via maven fixed the problem.
Edit: When I think about it, it might also have been a conflict between eclipse's auto-build and building via maven on the command line.