Java is the first usable object oriented commercial programming language.
The main reason I consider it usable is that it has a garbage collector. The second reason it is usable is that it is commercially acceptable.
It is not perfect, but the history of its development to date is reassuring.
The Cut The Crap Software provides a number of java packages to radically simplify the task to building computer systems.
The Generic Persistent Object model provides both persistence and a powerful object model - the first to correctly manage object associations.
The Alchemist is a code and system generator that builds on GPO to produce usable object models and web applications from a simple description.
Please check out the main website for more information and free downloads.