Synthesize impact of design refinements on object oriented software quality by reviewing available literature.
The correct answer and explanation is:
Correct Answer:
Design refinements in object-oriented software—such as improved class cohesion, minimized coupling, enhanced encapsulation, and better inheritance hierarchies—have a significant positive impact on software quality. Literature consistently shows that these refinements enhance maintainability, reusability, scalability, and overall system robustness.
300-Word Explanation:
In object-oriented (OO) software development, design refinements are critical to achieving and maintaining high software quality. These refinements involve iterative improvements in class design, object interaction, and architectural structure, often guided by software metrics and design principles such as SOLID.
One key refinement is increasing cohesion, where class responsibilities are focused and logically grouped. High cohesion improves understandability and maintainability. According to Chidamber and Kemerer’s metrics (1994), high LCOM (Lack of Cohesion in Methods) values are associated with poor design and higher fault-proneness.
Another refinement involves reducing coupling, particularly between classes (e.g., using the Coupling Between Objects (CBO) metric). Lower coupling leads to systems that are easier to modify and less error-prone. Studies (e.g., Briand et al., 1999) show that tightly coupled classes contribute to lower testability and reusability.
Encapsulation is another crucial principle. By hiding internal class details, developers can change internal logic without affecting external components. This increases system stability and flexibility. Similarly, the proper use of inheritance—without overuse or misuse—ensures polymorphism and reusability without introducing fragility (the so-called “fragile base class problem”).
Literature also supports using design patterns as part of refinement. Patterns like Factory, Observer, and Strategy improve modularity and adaptability. Empirical evidence (e.g., Gamma et al., 1994) shows that appropriate use of patterns can reduce development time and improve communication within teams.
In summary, available literature confirms that design refinements improve OO software quality by making systems more understandable, testable, maintainable, and scalable. These refinements, when guided by best practices and empirical metrics, lead to more robust and adaptable software systems.