OOP & Design Patterns - Abstraction - Abstract Class vs Interface - When to Use Which
In a system where a class hierarchy requires both shared code and multiple unrelated capabilities, which design approach best balances flexibility and code reuse?
In a system where a class hierarchy requires both shared code and multiple unrelated capabilities, which design approach best balances flexibility and code reuse?
hard⚖️ Approach Comparison Q8 of Q15
Step-by-Step Solution
Solution:
Step 1: Identify requirements
Shared code requires inheritance; multiple unrelated capabilities require multiple inheritance of contracts.Step 2: Evaluate options
Abstract classes allow code reuse but single inheritance only; interfaces allow multiple inheritance of contracts.Step 3: Best balance
Combining one abstract class for shared code with multiple interfaces for capabilities balances reuse and flexibility.Final Answer:
Option B -> Option BQuick Check:
Abstract class + interfaces enable code reuse and multiple capabilities [OK]
Quick Trick: Abstract class for code, interfaces for multiple contracts [OK]
Common Mistakes:
MISTAKES- Trying multiple abstract classes (not allowed)
- Ignoring code reuse by using only interfaces
- Using concrete base class limits flexibility
Trap Explanation:
PITFALL- Candidates often overlook single inheritance limits and misuse abstract classes for multiple capabilities.
Interviewer Note:
CONTEXT- Assesses ability to apply abstraction patterns in complex design scenarios.
Master "Abstraction - Abstract Class vs Interface - When to Use Which" in OOP & Design Patterns
Want More Practice?
15+ quiz questions · All difficulty levels · Free
Free Signup - Practice All QuestionsMore OOP & Design Patterns Quizzes