OOAD Interview Questions & Answers

Aggregation is the relationship between the whole and a part. We can add/subtract some properties in the part (slave) side. It won't affect the whole part. Best example is Car, which contains the wheels and some extra parts. Even though the parts are not there we can call it as car. But, in the case of containment the whole part is affected when the part within that got affected. The human body is an apt example for this relationship. When the whole body dies the parts (heart etc) are died

No, You cannot apply the link and Association interchangeably. Since link is used represent the relationship between the two objects. But Association is used represent the relationship between the two classes. link :: student:sangram course:MCA Association:: s tudent c o u r se

B e fore 1994 there were different methodologies like Rumbaugh, Booch, Jacobson, Meyer etc who followed their own notations to model the systems. The developers were in a dilemma to choose the method which best accomplishes their needs. This particular span was called as "method-wars"

Unified method is convergence of the Rumbaugh and Booch. Unified modeling lang. is the fusion of Rumbaugh, Booch and Jacobson as well as Betrand Meyer (whose contribution is "sequence diagram"). Its' the superset of all the methodologies.

The Three amigos namely, Ø James Rumbaugh (OMT): A veteran in analysis who came up with an idea about the objects and their Relationships (in particular Associations). Ø Grady Booch: A veteran in design who came up with an idea about partitioning of systems into subsystems. Ø Ivar Jacobson (Objectory): The father of USECASES, who described about the user and system interaction.

A Use Case is a description of a set of sequence of actions that a system performs that yields an observable result of value to a particular action. In SSAD process <=> In OOAD USECASE. It is represented elliptically.

An Actor is someone or something that must interact with the system.In addition to that an Actor initiates the process(that is USECASE).

Guard condition is one, which acts as a firewall. The access from a particular object can be made only when the particular condition is met.

I: :obj1 :o b j 2 II: :obj1 : o bj 2 In the above representation I, obj1 sends message to obj2. But in the case of II the data is transferred from obj1 to obj2.

This can be accomplished by specifying the relationship called "refinement” which talks about the two different abstraction of the same thing. Or example, calculate pay calculate class1 cl ass2 cla ss3