Errors running builder 'Maven project builder' on project XXX - Java.Lang.NullPointerException

If you installed STS on Eclipse and receive the following exception while trying to build a Spring project:

"Errors running builder 'Maven project builder' on project XXX - Java.Lang.NullPointerException"

then check whether you clearly installed related Maven plugin for your Eclipse instance (it is probably m2eclipse/Eclipse m2e, check the built path of your project). Probably you observe that it is not installed, so install and rebuilt your project (at least this is what happened in my case).