An internal error occurred during: “Updating Maven

Question

As the title mentioned I have the following problem: I use Eclipse with Maven Nature and when I update my Maven Project, I get this error:

An internal error occurred during: "Updating Maven Project".
Unsupported IClasspathEntry kind=4

The solution that always comes back is the following:

• rightclick project, remove maven nature
• mvn eclipse:clean (with project open in eclipse/STS)
• (sometimes they suggest to do mvn eclipse:eclipse next)
• rightclick project and reenable maven nature

Now I exhaustively tried all combinations several times. But I always keep getting the above error. The error starting occurring when I had to mvn eclipse:eclipse the project. Before it was always running fine using only m2eclipse features and setting everything in eclipse.

Answer 1

• I just went to Properties -> Java Build Path -> Libraries and removed the blue entries starting with M2_REPO.

• After that, I could use Maven -> Update Project again

Answer 2

This issue (https://bugs.eclipse.org/394042) is fixed in m2e 1.5.0 which is available for Eclipse Kepler and Luna from this p2 repo :

http://download.eclipse.org/technology/m2e/releases/1.5

If you also use m2e-wtp, you'll need to install m2e-wtp 1.1.0 as well :

http://download.eclipse.org/m2e-wtp/releases/luna/1.1

Answer 3

I had to do it slightly different to work for me:

1. rightclick project, remove maven nature (or in newer eclipse, "Maven->Disable Maven Nature")
2. mvn eclipse:clean (with project open in eclipse/STS)
3. delete the project in eclipse (but do not delete the sources)
4. Import existing Maven project

Answer 4

I solved this by looking at this comment on JBIDE-11655 : deleting all .project, .settings and .classpath in my projects folder.

Answer 5

I removed my .classpath file in my project directory to correct this issue. No need to remove the Maven Nature from the project in Eclipse.

The specific error I was getting was: Project 'my-project-name' is missing required Java project: 'org.some.package-9.3.0 But my project wasn't dependent on org.some.package in any way.

Perhaps an old version of the project relied on it and Maven wasn't properly updating the .classpath file.

Answer 6

I imported the project as general project from git repository.

• Deleted .settings, .project and .classpath in project's folder
• Configure -> Convert to Maven Project. Only this solved the problem in my case.