[eclipse] How to fix error "Updating Maven Project". Unsupported IClasspathEntry kind=4?

I have imported maven project in STS, when I run update update project I receive:

"Updating Maven Project". Unsupported IClasspathEntry kind=4

Is there a workaround for this?

1. Right-click on your project, select Maven -> Remove Maven Nature.

2. Open you terminal, go to your project folder and do mvn eclipse:clean

3. Right click on your Project and select “Configure -> Convert into Maven Project”

Now you got “Unsupported IClasspathEntry kind=4 Eclipse Scala” disappear.

Try mvn clean install eclipse:eclipse -Dwtpversion=2.0 command on DOS command prompt. Suggesting you because , It worked for me!!

I tried Marco's steps but no luck. Instead if you just get the latest m2e plugin from the link he provides and one by one right click on each project -> Maven -> Update Dependencies the error still pops up but the issue is resolved. That is to say the warnings disappear in the Markers view. I encountered this issue after importing some projects into SpringSource Tool Suite (STS). When I returned to my Eclipse Juno installation the warnings were displaying. Seeing that I had m2e 1.1 already installed I tried Marco's steps to no avail. Getting the latest version fixed it however.

Upgrading from Kepler to Luna worked for me.

I had just added some components for Java 1.8 support. It seems that they where not as compatible as I would like or that I mixed the wrong ones. It really caused a lot of problems. Trying to update the system reported errors as they couldn't fulfill some dependencies. Maven upgrades didn't work. Tried a lot of things.

So, if there is no reason to avoid the upgrade just add the luna repository to avalilable software sites (Luna http://download.eclipse.org/releases/luna/ ) and "check for updates". It is better to have all the components with the same version and there are some nice new features.

Seeing all other answers. I found for me a simpler way.

I just removed all lines in the .classpath (editing with eclipse) containing a var and used maven -> update project without an error.

This error is also thrown if the update command is used on a project instrumented for code coverage with Clover.

To resolve in this scenario: Un-instrument the project folders you wish to update. Run the maven update then instrument for code coverage again.

Have you tried:

1. If you have import project into the eclipse 4, please delete it.
2. In maven consol, run: mvn eclipse:clean
3. In Eclipse 4: File -> Import -> Maven -> Existing Maven Projects

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

1. Make sure that the version of the m2e(clipse) plugin that you're running is at least 1.1.0

2. Close maven project - right click "Close Project"

3. Manualy remove all classpathentry with kind="var" in .classpath file
4. Open project

or

1. Remove maven project
2. Manualy rmeove .classpath 4 Reimport project

Before importing the project, it should be converted into eclipse project mvn eclipse: eclipse Then i found the following error. An internal error occurred during: "Importing Maven projects".Unsupported IClasspathEntry kind=4

Where is the value kind = "var" that M2E does not recognize and therefore throws the error.

Now type this. mvn eclipse: clean

Now refresh the project in eclipse or re-import.

I'm using Eclipse 4.3.2 (Kepler) with M2E 1.4.x and felt over this problem several times!

In my case the "mvn eclipse:eclipse" command also generates Checkstyle, PMD and Findbugs configuration so "mvn eclipse:clean" does not help me because it drops all those config files again.

The best solution for me was to delete all ".classpath" files:

find . -name ".classpath" -delete

and import the project into eclipse afterwards.

Sometimes, even re-importing the Maven project will not work. Updating the project correctly in eclipse is not a deterministic process. The only 100% fail safe procedure I've found is:

1. Disable Maven Nature, run mvn eclipse:clean, restart, cross your fingers and Pray 3 times.
2. If this won't work, delete the project, run mvn eclipse:clean, re-import refresh, pray and use the force.
3. If this still doesn't work, restart Eclipse, or even better your computer. While waiting for the reboot, you can make a random donation to fix your Karma. Repeat step 2 and don't forget to pray and control your anger. Anger leads to hate. Hate leads to suffering.
4. Try all the other answers posted in this thread. You might need to try them all for 3 times at least before giving up.
5. Format your Computer, re-install Eclipse and Maven. No need to pray anymore, all gods hate you anyway
6. Delete your git project, burn the physical drive that stored the remote repository, and write your project from scratch.
7. Find a time machine, travel to the past and convince yourself to follow another, non-programming career or at least to avoid Java

I couldn't get mvn eclipse:clean etc to work with Kepler.

However I changed creating and extending variables to just using external jars in my eclipse classpath. This was reflected in no var's in my .classpath.

This corrected the problem. I was able to do a Maven update.

I tried all the steps mentioned here and on similar questions but couldn't solve this problem. I could neither solve problem nor update my m2eclipse. So I installed Eclipse Luna and it solved my problem... though it mean that I had to spend about 45 min to configure all the environment in my workspace.