They claim that the OO approach simplifies the transitions in system development stages, enhances communication between users and developers, encourages code reuse and enables the creation of robust information systems which can be easily upgraded and maintained. The Hybrid Approach We propose a hybrid methodology for the development of business-oriented information systems, which combines the functional approach and the OO approach. It is therefore worthwhile, on the one hand, that analysis be made through DFDs which express the functional requirements of the system. On the other hand, the design should be made through the OO approach to facilitate the transition of the design to OO programming, which proved to be a better approach to implement software. The data stores which were identified during functional analysis and appear in the DFDs are translated into an object schema.
Every data store is translated into one or more object classes.
Recall that a transaction performs various types of operations. Each such operation is removed from the body of the transaction and attached to an appropriate object class. Hence, the methods that belong to each object class are derived from the transactions that access it. Finally, the transactions, the object classes and the user-interface can be implemented with an OO programming environment. Design of the object schema follows the analysis, after having identified the data stores and the data elements that flow in and out.