[m2e-users] Could not get the value for parameter X for plugin Y

[Alexandros Karypidis <akarypid@xxxxxxxx>]

Hi all,

I've been using Eclipse 4.9 on my maven project with no issues for a while. Recently I upgraded to 4.12 and ran into a problem. I downgraded to 4.11 thinking it's some new bug with the 2019-06 release but the same problem persists. So for a couple of plugin executions, m2e complains about the parameters. One of them is an xtend compiler plugin (language parameters) and the other is luckily (I can give an example and simple reproduce steps, see below) the very basic maven dependency plugin.

My project works fine in 4.9 and also from command line with various maven versions. I was using 3.5.3 and also upgrade to 3.6.1 to test and did not have any issue.

I posted details in eclipse forums here: https://www.eclipse.org/forums/index.php/t/1099526/

Basically, I reproduce it quite easily as follows:

1. creating a new Maven project (tick simple checkbox to skip archetype selection)
2. edit pom.xml in new project and add an execution for maven-dependency-plugin to copy some random artifact
3. update maven project configuration

I get:

org.eclipse.core.runtime.CoreException: Could not get the value for parameter artifactItems for plugin execution copy-libraries
    at org.eclipse.m2e.core.internal.embedder.MavenImpl.getMojoParameterValue(MavenImpl.java:936)
    at org.eclipse.m2e.core.internal.embedder.MavenImpl.lambda$5(MavenImpl.java:944)
    at org.eclipse.m2e.core.internal.embedder.MavenExecutionContext.executeBare(MavenExecutionContext.java:177)
    at org.eclipse.m2e.core.internal.embedder.MavenExecutionContext.execute(MavenExecutionContext.java:112)
    at org.eclipse.m2e.core.internal.embedder.MavenImpl.getMojoParameterValue(MavenImpl.java:943)
...
    at org.eclipse.core.internal.events.AutoBuildJob.run(AutoBuildJob.java:244) at org.eclipse.core.internal.jobs.Worker.run(Worker.java:63)

Caused by: org.codehaus.plexus.component.configurator.ComponentConfigurationException: Cannot determine child type
    at org.codehaus.plexus.component.configurator.converters.composite.AbstractCollectionConverter.getChildType(AbstractCollectionConverter.java:110)
    at org.codehaus.plexus.component.configurator.converters.composite.AbstractCollectionConverter.fromChildren(AbstractCollectionConverter.java:52)
    at org.codehaus.plexus.component.configurator.converters.composite.CollectionConverter.fromConfiguration(CollectionConverter.java:68)
    at org.codehaus.plexus.component.configurator.converters.composite.CollectionConverter.fromConfiguration(CollectionConverter.java:47)
    at org.eclipse.m2e.core.internal.embedder.MavenImpl.getMojoParameterValue(MavenImpl.java:932)
... 30 more
Caused by: java.lang.ClassNotFoundException: org.apache.maven.plugin.dependency.fromConfiguration.Item
    at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:50)
    at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadClass(ClassRealm.java:271)
    at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:247)
    at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:239)
    at org.codehaus.plexus.component.configurator.converters.composite.AbstractCollectionConverter.getChildType(AbstractCollectionConverter.java:87) ... 34 more