Transfer 'ContextMatrixModel' in its own file
Make 'ContextMatrix', 'ContextMatrixModel' & 'View.View' public
Move context editor related classes into the package 'contexteditor'
Delete 'AppTest'

You need to look at how to add Unit Tests to Maven project. There is a specific convention.
This is why there is a dedicated folder 'src/test'.
Transfer 'Util' to the top-level package