Oracle ADF samples http://weblog.singhpora.com/
To download all samples, use this link: https://github.com/jvsingh/bitesizedadf/archive/master.zip
This is a very simple example to apply some basic concepts (the role of a layered architecture, MVC, Data controls, entity objects and more.) Details here: http://weblog.singhpora.com/2013/12/adf-ui-with-mongodb-for-persistence.html