Using an Object-Oriented Development Approach

You can employ object-oriented development methods that incorporate UML concepts and also provide you with an iterative, procedural framework within which to work.

For detailed information on object-oriented development processes, refer to the list of publications in the section Rose Expert Development Related Information. Of particular interest in this context is the approach called Object Oriented Software Engineering (OOSE) because of the focus on use case models as a leading principle in development.

Here, we review the generic object-oriented development process.

In general, the object-oriented development process tends to be iterative. That is, you develop an application in successive stages-each time getting closer to the ideal. First you develop a core application-an initial prototype. Then you refine the prototype, improving and extending it. Depending on the complexity of the application, you may go through many cycles or iterations.

This process usually consists of the following phases, wherein you begin at a high level of abstraction and get progressively more specific in describing the system you want to build:

• Define Requirements. What does the application need to do? What is the problem? This phase might involve use cases, scenarios, business process re-engineering studies, or CRC cards. The result is a requirements specification, a document that describes the application to be developed.

• Perform Analysis. Provide a high-level description of the types of objects that need to be represented and the logical relationships between them. You might use class diagrams and sequence diagrams, and to a lesser degree collaboration diagrams and the state diagrams when you need to define a specific object or interaction in greater detail.

• Design. Describe the physical layout of the system. Extend the diagrams you used in the Analysis phase and add infrastructure. The goal is to specify all the objects in the system, and identify all the attributes and most of the operations.

• Implementation. Translate the design model into code. The class structures and names that you have created during the analysis and design phase become code elements during the coding phase.

• Test. Test the executable code.

Generally, you will cycle through the last four steps several times as shown in Figure 2-1.

Figure 2-1 Iterative Nature of the Objected Oriented Development Process