If an interviewer asks you to extend a class with private fields but no setters, how would you safely allow controlled modification of those fields in a subclass?

hard🎤 Interviewer Follow-up Q10 of Q15

OOP & Design Patterns - Encapsulation - Data Hiding, Getters/Setters & Access Modifiers

AChange the private fields to public in the superclass

BAdd protected or public setter methods in the superclass for controlled access

CDirectly access and modify private fields in the subclass using reflection

DDuplicate the fields in the subclass and manage them independently

Step-by-Step Solution

Solution:

Step 1: Understand subclass access constraints
Private fields are inaccessible; adding protected/public setters in superclass allows controlled subclass modification.
Final Answer:
Option B -> Option B
Quick Check:
Protected setters enable safe subclass access [OK]

Quick Trick: Use superclass setters for subclass access [OK]

Common Mistakes:

MISTAKES

Making fields public breaks encapsulation
Using reflection is unsafe and discouraged
Duplicating fields causes inconsistency

Trap Explanation:

PITFALL

Candidates may suggest unsafe or bad practices instead of proper accessor methods.

Interviewer Note:

CONTEXT

Tests deep understanding of encapsulation and inheritance interplay.

Master "Encapsulation - Data Hiding, Getters/Setters & Access Modifiers" in OOP & Design Patterns

2 interactive learning modes - each teaches the same concept differently

Solution Trace

Want More Practice?

15+ quiz questions · All difficulty levels · Free

Free Signup - Practice All Questions

More OOP & Design Patterns Quizzes

If an interviewer asks you to extend a class with private fields but no setters, how would you safely allow controlled modification of those fields in a subclass?

Step 1: Understand subclass access constraints

Final Answer:

Quick Check:

Want More Practice?