Open Xava - Business Component Versus MVC

Business Component Versus MVC

A business component includes all software artifacts needed to define a business concept. OpenXava is a business component framework because it allows defining all information about a business concept in a single place. For example, for defining the concept of Invoice, in OpenXava a single file (Invoice.java) is used, and all information about invoice concept (including data structure, user interface layout, mapping with database, validations, calculations, etc.) is defined there.

In a MVC framework the business logic (the Model), the user interface (the View) and the behavior (the Controller) are defined separately. These types of frameworks are useful if the rate of change of logic and data structures is low and the possibility of changing user interface technology or data access technology is high.

In OpenXava, the addition of a new field to an Invoice only requires changing a single file: Invoice.java. But MVC frameworks are cumbersome when changes to structure and data are very frequent (as in the business application case). Imagine the simplest change, adding a new field to an Invoice. In the MVC framework the developer must change three sections: the user interface, the model class and the database table. Moreover if the developer uses Java EE design patterns he has to change the DTO class, the Facade Session Bean, the Entity Bean mapping, etc.

Using OpenXava makes it possible to allocate the development work using a business logic oriented task distribution. For example Invoice to one developer, Delivery to another, as opposed to technology layer business logic to one developer, user interface to another.