Object Oriented Analysis vs Object Oriented Design

Tuesday, June 3, 2008

Why software engineers are paid more?
Software engineers are modeling projects whereas engineers are building projects. Developing a Software Project is much more complex than the developing any other tangible project like building. Since the nature of intangibility of software, it is very harder to monitor and measure the progress of software project.

• Complexity of the problem domain
The domains can vary really vastly in a software problem. If the problem could be solved simply and easily by human, then there is no need for a software system. It is clearly obvious that we have so much software systems because of the complexity of the problem domain.

• Impedance Mismatch
The system developer and the architect of the system doesn’t know what the client really wants and the client also is not clear what he needs with his requirement.
So vague ideas and communication gap ends with the project in mismatching situation.

• Difficulty of managing the development process
Software is a total intangible product/Service. It is hard to measure and value in a quantitative manner. Qualitatively only we can get at the needed milestones and achievements in a software process.
Software development process is also a intangible process with lot of inconsistencies. There is no clear cut benchmark to evaluate the progress and the management.

AbstractionFind out the special characteristics of an object that can be that can distinguish it form the other objects with the clear boundaries relative to the viewer. Recognition of the similarities of the objects is important to distinguish the objects. This should be a simple specification where the details are emphasized on the importance to the user. Entity abstraction (Considering the properties of objects), Action abstraction (Considering the functionality of the object), Virtual machine abstraction (Set of similar objects represented as one due to abstraction level) and coincidental abstraction (Non similar objects represented as one) are some abstraction types

Encapsulation putting the properties and the factions together in a single module without having it to depend on the other such modules internal values; This serves the actual implementation of the abstraction. Also allows to hide the details of implementation.

Modularity- This is to group the factions in to a components which are loosely coupled and they should have the ability to work independently. Reduces the cost of software redesign and modules can be reused.

HierarchyIs the ordering of the abstractions in to a tree like structure. There are two types of Hierarchy’s is a and part of. As a example wheel is a part of the car and ford is a type of a car.

W.R.V.G.I.R Kumara (044051)