Buddhists talk about Three Gems:
- Buddha: the enlighten one
- Dhamma: teaching
- Sangha: literally means ‘community’ or ‘assembly.’
Here are similar thing for Object- Orientation. The difference is the later are strictly non religious, but there in spite of this some similarity and that is the belief in one’s own case. These are:
- The paradigm
- The abstract business model
- The agile incremental 3-tier application development
The paradigm: To know and understand the OO- principles and also to understand it paradigmatic nature. This means that the world is perceived abstractly as a set of objects such that:
* all of them have two aspects: structure ans behavior
* they can collaborate with ease other
* there is no other kind of action possible in the world
The abstract business model: The development has to be started with creating an abstract domain model from scratch. Of cause one can use for this something like the business line models as I have presented here as a starting point. But even then every class have to be evaluated and checked that it is defined to this company and describes the current reality correctly. The model have to have all essential business behavior embedded in the model. The most important aspects in the model are objectified events, there behavior and object associations.
The agile incremental 3-tier application development: To succeed in this phase is crucial.
To continue this line of simplicity the architectural structure is the final cornerstone of this application. The maxim simplicity is achieved when the implementation keeps the three aspect: 1) application functionality, 2) domain functionality and 3) object persistence as separate as possible. Here a must is that domain objects have no functional references anywhere outside the domain itself. There are minimal references from application layer to into the domain. And the domain objects should have one references each to outside service that provide the persistence. The optimal solution would be such that the object virtual machine provides that service automatically into an object database.
This is the final phase to really deliver the concrete application. Next important aspect is to create the application incrementally and iteratively. One mustunderstand that the abstract domain model from previous steps is more of a starting point than end result which will grow in size during the development. On the other hand it is vitally important the first model is relatively small and thus will clearly describe the most important structures and behavior. This means that this model should have most of the structures present ie. most classes and associations are present but major part of attributes can still be lacking.
Done this way yield to minim solution thus minim amount of work and this enables indirectly maxim quality through simplicity.
The most is achieved when the model covers all activities of the company and the application layer is a comprehensive operation management and control of the company ( like ERPs today)