Which design pattern describes creating objects through a separate component to encapsulate instantiation, as seen in MIPC data access object creation?

• A. Visitor pattern
• B. Strategy pattern
• C. Factory pattern
• D. Decorator pattern

Answer: (C)

The main idea here is separating object creation from the rest of the code by using a dedicated component to instantiate objects. This is the essence of the Factory pattern: a factory (a class or method) is responsible for producing instances, often returning them via a common interface rather than exposing concrete classes.

In the MIPC data access scenario, your business logic works with a DAO interface, while the actual DAO implementation that talks to a database (or a mock for tests) is created by a factory. The caller asks the factory for a DAO, and the factory decides which concrete class to instantiate and return. This keeps the creation details in one place, so you can swap implementations, switch data sources, or supply mocks without changing the rest of the code.

This approach centralizes and hides how objects are constructed, which is especially helpful when the creation process is complex or varies by configuration. Variants like simple factory methods, factory methods, or abstract factories all revolve around providing a controlled way to produce objects, instead of calling new directly.

Other patterns focus on different goals: the Visitor pattern operates on elements of a structure, the Strategy pattern selects among algorithms at runtime, and the Decorator pattern adds behavior to objects dynamically. None centers on object creation in the same way, which is why the Factory pattern is the best fit here.