SCWCD Exam, design patterns questions

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These 2 are from design patterns.


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Questions
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1. What are the benefits of using the Transfer Object pattern? (Select two)

a) The type of the actual data source can be specified at deployment time.
b) The data clients are independent of the data source vendor API.
c) It increases the performance of data-accessing routines.
d) It allows the clients to access the data source through EJBs.
e) It allows resource locking in an efficient way.


2. Which design pattern allows you to decouple the business logic, data representation,
and data presentation? (Select one)

a) Model-View-Controller
b) Transfer Object
c) Bimodal Data Access
d) Business Delegate


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Answers
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1) correct answer: both a) and b)

Explanation:
This pattern is used to decouple business logic from data access logic. It hides the data access mechanism from the business objects so that the data source can be changed easily and transparently to the business objects.

2) correct answer: a)

Explanation:
In the Model-View-Controller pattern, Model is the data representation, View is the data presentation, and Controller is the implementation of business logic. Therefore, a is the correct answer.