M2Eclipse Error : Unsupported IClasspathEntry kind=4

“Updating Maven Project”. Unsupported IClasspathEntry kind=4

 

The good news :  we have an effective workaround. It occurs when you use the eclipse:eclipse goal using the Maven dos command. When m2e plugin encounters a "var" classpathentry, it throws the error : Unsupported IClasspathEntry kind=4

 

The solution is  :

1. Make sure you have the latest version of m2e plugin. At least 1.1.0. The update site ishttps://repository.sonatype.org/content/repositories/forge-sites/m2e/
2. Disable the maven nature of the related project using the menu Maven -> Disable Maven Nature
3. Using the command line execute a mvn eclipse:clean
4. Re-enable the maven nature using the menu Configure -> Convert to Maven Project

参考： http://happy-coding.org/updating-maven-project-unsupported-iclasspathentry-kind4/