Dependency Injection is easier to implement, than to explain. In this 8 minute-screencast I explained what happens behind the scenes within an application server during initialization:
The screencast is actually the first 10 minutes of the airhacks.com workshop (Bootstrap). For unknown reasons, I referred to "side" with "size".I was too lazy to re-record it and recognized it after the fact...
Because DI is so easy, I built an injection "framework" for JavaFX: http://afterburner.adam-bien.com
See you at Java EE Workshops at MUC Airport!
Online workshop: Java EE 7 Bootstrap