It’s somehow annoying when I got this error in Unity:
unity Exception in thread “main” java.lang.NoClassDefFoundError: javax/xml/bind/annotation/XmlSchema
I got this error when I tried to add new GoogleMobileAds package to Unity. I got the error when I build my project.
After googling around, finally the solution that worked for me is to uninstall my current JDK which is version 13, and I reinstall the older one version 8.
If you got this error, try to use JDK 8 instead of higher version of it.