UA

Unified Approach ( UA ) It combines best practices, methods process, guidelines & methodology (Rumbaugh, Booch and Jacobson) along with UML notations and diagrams for better understanding object-oriented concepts and s/m development.

It has the following processes and concepts Use case driven development O.O. analysis O.O. design Incremental development & Prototyping Continuous testing.

The methods & technology employed include: UML used for modeling Layered approach Repository for O.O. s/m develoment patterns & frameworks. Component based Development.

O-O ANALYSIS It is the process of understanding the user’s needs, problem domain and s/m responsibilities. Steps: 1.Identify actors 2.Develop business process model using UML activity diagram. 3.Develop usecase 4.Develop interaction diagram 5.Identify classes.

O-O DESIGN By following Jacobson life cycle model, we can produce designs that are traceable across requirements,analysis,design,coding and testing. Steps: 1.Designing classes,attributes,methods,association, structures and protocols,design axioms. 2.Design access layer. 3.Design & prototype user interface. 4.User satisfaction and usability test. 5.Iterate and refine the design.

ITERATIVE DEVELOPMENT AND CONTINUOUS TESTING You must iterate and reiterate until, you are satisfied with the s/m. Continue the refining cycle throgh the development process until, you are satisfied with the results. During iteative process, your prototypes will be transformed into actual application. Usage scenarois can become test scenarios.

MODELING BASED ON UML UML combines the best notations of three methodologies. It is the universal language for modeling s/m. UA uses the UML to describe and model the analysis and design phases of s/m development.

UA REPOSITORY REUSABILITY ( use or reuse ) It should be accessible to many people. It should be easy to search the repository for classes based on their attributes, methods or other characteristics.

LAYERED APPROACH Two-layer architecture: e.g client–server application.(refer book for diagram) User interface screens are tied with data through routines that sit directly behind the screens. The objects can not be reused in other projects.

( refer book for diagram ) This architecture isolates the functions of the interface from functions of the business. This approach isolates the business from details of data access.

Three-layer architecture: It has 3 layers ( refer book for diagram ) 1.user interface layer(view) 2.Business layer 3.Access layer Here the objects are independent with each other.

Business layer: It has business objects. These objects should not be responsible for following: 1.display details. 2.data access details Business model captures the static(association & aggregation) & dynamic (how the business objects interact to perform tasks) relationship among a collection of business objects.

View Layer: This is responsible for following: 1.responding to user interaction view layer objects must be designed to traslate actions (by the user) such as clicking,selecting menu into an appropriate response. That response may be to open or close another interface or to send a message to business layer to start some business process. 2.Displaying business objects View layer must paint the possible picture of business objects for the user.

Access Layer: This objects know how to communicate with the place where the data actually reside, whether it be a database,internet or file. It has 2 responsibilities. 1.Traslate Request This layer traslates request from business layer into appropriate protocol for data access 2.Traslate Result This layer traslates the data retrieved, back to appropriate business objects and pass those objects to business layer.