NPE when importing existing Maven project

Scott,

can you try with the latest 0.9.7 dev build? WTP support has changed significantly since 0.9.6.

regards,

Fred Bricon

Getting this same error using 0.9.7.200810211352 (and WTP 3.0.2) with Checking out a Maven project from SCM.

The project modules still appear to be created, but Eclipse project configuration appears incomplete (can't resolve references). By invoking "Update Project Configuration" on each module, I can eventually get a working project.

David,

Resolution is postponed to 0.9.8. as I couldn't reproduce the bug on 0.9.7.200810211352 w/ Ganymede SR1 and WTP 3.0.2 with the attached pom.xml. The project was created normally.
You seem to use a multi project configuration. Could you attach a test project with modules reproducing this bug?

regards,

Fred Bricon

In my case, the errors were caused by "maven-eclipse-plugin"

Removing maven-eclipse-plugin resolved the error. (I believe there are known incompatibilities).

To reproduce:
1. unzip attached mngeclipse-1009.zip
2. uncomment maven-eclipse-plugin in "ic/ic-web/pom.xml"
3. import maven project

Results in:

!SESSION 2008-11-12 16:55:06.817 -----------------------------------------------
eclipse.buildId=M20080911-1700
java.version=1.6.0_10
java.vendor=Sun Microsystems Inc.
BootLoader constants: OS=win32, ARCH=x86, WS=win32, NL=en_US
Framework arguments: -Xmx512m
Command-line arguments: -os win32 -ws win32 -arch x86 -Xmx512m -data C:\workspace2

!ENTRY org.eclipse.core.resources 4 1 2008-11-12 17:07:08.420
!MESSAGE Internal Error
!STACK 0
java.lang.IllegalArgumentException: Element not found: /ic/ic-web/.settings.
at org.eclipse.core.internal.watson.ElementTree.elementNotFound(ElementTree.java:255)
at org.eclipse.core.internal.watson.ElementTree.createElement(ElementTree.java:183)
at org.eclipse.core.internal.resources.Workspace.createResource(Workspace.java:861)
at org.eclipse.core.internal.resources.Workspace.createResource(Workspace.java:816)
at org.eclipse.core.internal.localstore.RefreshLocalVisitor.createResource(RefreshLocalVisitor.java:80)
at org.eclipse.core.internal.localstore.RefreshLocalAliasVisitor.createResource(RefreshLocalAliasVisitor.java:37)
at org.eclipse.core.internal.localstore.RefreshLocalVisitor.synchronizeExistence(RefreshLocalVisitor.java:216)
at org.eclipse.core.internal.localstore.RefreshLocalVisitor.visit(RefreshLocalVisitor.java:290)
at org.eclipse.core.internal.localstore.UnifiedTree.accept(UnifiedTree.java:102)
at org.eclipse.core.internal.localstore.FileSystemResourceManager.refreshResource(FileSystemResourceManager.java:759)
at org.eclipse.core.internal.localstore.FileSystemResourceManager.refresh(FileSystemResourceManager.java:743)
at org.eclipse.core.internal.resources.Resource.refreshLocal(Resource.java:1479)
at org.maven.ide.eclipse.project.configurator.MavenProjectConfigurator.configure(MavenProjectConfigurator.java:78)
at org.maven.ide.eclipse.internal.project.ProjectConfigurationManager.updateProjectConfiguration(ProjectConfigurationManager.java:231)
at org.maven.ide.eclipse.internal.project.ProjectConfigurationManager.configureNewMavenProject(ProjectConfigurationManager.java:185)
at org.maven.ide.eclipse.internal.project.ProjectConfigurationManager.importProjects(ProjectConfigurationManager.java:143)
at org.maven.ide.eclipse.wizards.MavenImportWizard$1.runInWorkspace(MavenImportWizard.java:94)
at org.eclipse.core.internal.resources.InternalWorkspaceJob.run(InternalWorkspaceJob.java:38)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)

!ENTRY org.eclipse.core.jobs 4 2 2008-11-12 17:07:08.920
!MESSAGE An internal error occurred during: "Importing Maven projects".
!STACK 0
java.lang.NullPointerException
at org.eclipse.wst.common.componentcore.internal.resources.VirtualComponent.setReferences(VirtualComponent.java:363)
at org.maven.ide.eclipse.wtp.WebProjectConfiguratorDelegate.setModuleDependencies(WebProjectConfiguratorDelegate.java:118)
at org.maven.ide.eclipse.wtp.WTPProjectConfigurator.mavenProjectChanged(WTPProjectConfigurator.java:55)
at org.maven.ide.eclipse.project.configurator.AbstractProjectConfigurator.mavenProjectChanged(AbstractProjectConfigurator.java:108)
at org.maven.ide.eclipse.internal.project.ProjectConfigurationManager.mavenProjectChanged(ProjectConfigurationManager.java:576)
at org.maven.ide.eclipse.internal.project.MavenProjectManagerImpl.notifyProjectChangeListeners(MavenProjectManagerImpl.java:692)
at org.maven.ide.eclipse.internal.project.ProjectConfigurationManager.configureNewMavenProject(ProjectConfigurationManager.java:189)
at org.maven.ide.eclipse.internal.project.ProjectConfigurationManager.importProjects(ProjectConfigurationManager.java:143)
at org.maven.ide.eclipse.wizards.MavenImportWizard$1.runInWorkspace(MavenImportWizard.java:94)
at org.eclipse.core.internal.resources.InternalWorkspaceJob.run(InternalWorkspaceJob.java:38)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)

!ENTRY org.maven.ide.eclipse 4 0 2008-11-12 17:07:11.840
!MESSAGE
!STACK 0
java.lang.NullPointerException
at org.eclipse.wst.common.componentcore.internal.resources.VirtualComponent.setReferences(VirtualComponent.java:363)
at org.maven.ide.eclipse.wtp.WebProjectConfiguratorDelegate.setModuleDependencies(WebProjectConfiguratorDelegate.java:118)
at org.maven.ide.eclipse.wtp.WTPProjectConfigurator.mavenProjectChanged(WTPProjectConfigurator.java:55)
at org.maven.ide.eclipse.project.configurator.AbstractProjectConfigurator.mavenProjectChanged(AbstractProjectConfigurator.java:108)
at org.maven.ide.eclipse.internal.project.ProjectConfigurationManager.mavenProjectChanged(ProjectConfigurationManager.java:576)
at org.maven.ide.eclipse.internal.project.MavenProjectManagerImpl.notifyProjectChangeListeners(MavenProjectManagerImpl.java:692)
at org.maven.ide.eclipse.internal.project.MavenProjectManagerImpl.refresh(MavenProjectManagerImpl.java:361)
at org.maven.ide.eclipse.internal.project.MavenProjectManagerRefreshJob.run(MavenProjectManagerRefreshJob.java:88)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)

Fred,
Maybe reassign this to Scott to check if the project he was importing had also included "maven-eclipse-plugin"? If so, could probably close this.

Regards
David.

David

Indeed the bug is caused by maven-eclipse-plugin which mess with the project configuration file during m2eclipse configuration.
Its use should be avoided when working with m2eclipse'd projects.

On the other hand, errors could be handled more elegantly in org.maven.ide.eclipse.project.configurator.MavenProjectConfigurator.configure() , instead of just logging errors (eg.: prevent further configuration? add an error marker on the project?).

JIRA Issues cannot be attributed to non developers, but their reporter can still close them.

@Scott : could you give us an update on your configuration? do you use maven-eclipse-plugin ? Have you tried the latest 0.9.7.x version? if the bug still occurs, can you attach a test project and a quick how-to to reproduce it? Thanks.

regards,

Fred Bricon

Thanks Fred.

Regarding the incompatibility with maven-eclipse-plugin, we might need to update Install Requirements documentation about this too.

Apart from this line in the FAQ, it's difficult to know this causes problems. ( "As of maven-eclipse-plugin-2.3 its dependency management is incompatible with m2eclipse and is waiting for the patches to be applied. See MECLIPSE-78.")

Cheers,
David.