I have Eclipse (Juno SR2) with both M2E (1.3), M2E-WTP (0.17) and WebSphere Dev Tools for v.8. The problem started after Websphere Dev tools installation. It says in error dialog : "Validating" "org/eclipse/m2e/wtp/MavenWtpPlugin".
In Eclipse logs it turned out to be NoClassDefFoundError
!MESSAGE An internal error occurred during: "Validating <module name here>".
!STACK 0
java.lang.NoClassDefFoundError: org/eclipse/m2e/wtp/MavenWtpPlugin
Does anyone had some luck in solving this issue?
Thanks!
The missing class is in fact there, plugin org.eclipse.m2e.wtp. Started to dig in the IBM WAS Dev Tools.
The problem originates from com.ibm.etools.maven.javaee.core plugin.
Checked MANIFEST.MF under \plugins\com.ibm.etools.maven.javaee.core_1.1.0.v20130522_1924\ and it turned out there is some strange version range bundle dependency on org.eclipse.m2e.wtp;bundle-version="[1.0.0,2.0.0)";resolution:=optional. The plugin org.eclipse.m2e.wtp version is not even close to version 1.0.0 and resolution is optional, so made some changes to conform the bundle resolution:
...,org.eclipse.m2e.wtp;bundle-version="[0.1.0,2.0.0)";resolution:=optional,...
Started Eclipse with -clean argument, and refreshed all Maven projects in the workspace.
This seems to do the trick for me. You may still get
"Updating Maven Project". Unsupported IClasspathEntry kind=4
but there is a fix for this already here "Updating Maven Project". Unsupported IClasspathEntry kind=4