OBJECT-ORIENTED METHODOLOGIES

use cases also are the ones that have uses or extends relationships. Sahaj Computer Solutions 24 Object Oriented Systems Development Object-Oriented Software Engineering: Objectory Object-oriented software engineering (OOSE), also called Objectory, is a method of object-oriented development with the specific aim to fit the development of large, real-time systems. The development process, called use-case driven development, stresses that use cases are involved in several phases of the development , including analysis, design, validation, and testing. Sahaj Computer Solutions 25 Object Oriented Systems Development Object-Oriented Software Engineering: Objectory The use-case scenario begins with a user of the system initiating a sequence of interrelated events. The system development method based on OOSE, Objectory, is a disciplined process for the industrialized development of software, based on a use-case driven design. It is an approach to object-oriented analysis and design that centers on understanding the ways in which a system actually is used. Sahaj Computer Solutions 26 Object Oriented Systems Development Object-Oriented Software Engineering: Objectory Objectory is built around several different models: ◦ Use case-model.The use-case model defines the outside (actors) and inside (use case) of the system's behavior. ◦ Domain object model. The objects of the "real" world are mapped into the domain object model. ◦ Analysis object model. The analysis object model presents how the source code (implementation) should be carried out and written. ◦ Implementation model. The implementation model represents the implementation of the system. ◦ Test model. The test model constitutes the test plans, specifications, and reports. Sahaj Computer Solutions 27 Object Oriented Systems Development Object-Oriented Business Engineering Object-oriented business engineering (OOBE) is object modeling at the enterprise level. Use cases again are the central vehicle for modeling, providing traceability throughout the software engineering processes. Sahaj Computer Solutions 28 Object Oriented Systems Development Object-Oriented Business Engineering Analysis phase: ◦ The analysis phase defines the system to be built in terms of the problem-domain object model, the requirements model, and the analysis model. ◦ The analysis process should not take into account the actual implementation environment. ◦ This reduces complexity and promotes maintainability over the life of the system, since the description of the system will be independent of hardware and software requirements. ◦ The analysis process is iterative but the requirements and analysis models should be stable before moving on to subsequent models. ◦ Jacobson et al. suggest that prototyping with a tool might be useful during this phase to help specify user interfaces. Sahaj Computer Solutions 29 Object Oriented Systems Development Object-Oriented Business Engineering Design and implementation phases. ◦ The implementation environment must be identified for the design model. ◦ This includes factors such as Database Management System (DBMS), distribution of process, constraints due to the programming language, available component libraries, and incorporation of graphical user interface tools. ◦ It may be possible to identify the implementation environment concurrently with analysis. ◦ The analysis objects are translated into design objects that fit the current implementation environment. Sahaj Computer Solutions 30 Object Oriented Systems Development Object-Oriented Business Engineering Testing phase. ◦ Finally, Jacobson describes several testing levels and techniques. ◦ The levels include unit testing, integration testing, and system testing. Sahaj Computer Solutions 31 Object Oriented Systems Development