Bird
0
0

Which method signature correctly belongs to a Command interface supporting undo?

easy🧠 Conceptual Q12 of 15
LLD - Design — Tic-Tac-Toe Game
Which method signature correctly belongs to a Command interface supporting undo?
Avoid save(); void load();
Bvoid execute(); void undo();
Cvoid start(); void finish();
Dvoid run(); void stop();
Step-by-Step Solution
Solution:

  1. Step 1: Identify standard Command interface methods

    The Command pattern typically defines an execute() method to perform the action and an undo() method to reverse it.

  2. Step 2: Match method signatures

    Only void execute(); void undo(); has execute() and undo(), matching the Command pattern for undo.

  3. Final Answer:

    void execute(); void undo(); -> Option B

  4. Quick Check:

    Command methods = execute and undo [OK]
Quick Trick: Look for execute() and undo() methods [OK]
Common Mistakes:
MISTAKES
  • Choosing unrelated method names like run/stop
  • Confusing start/finish with undo functionality
  • Assuming save/load are Command methods

Want More Practice?

15+ quiz questions · All difficulty levels · Free

Free Signup - Practice All Questions
More LLD Quizzes
Behavioral Design Patterns — Part 1 - Why behavioral patterns define object interaction - Quiz 10hard Behavioral Design Patterns — Part 1 - Strategy pattern - Quiz 10hard Behavioral Design Patterns — Part 1 - Observer pattern - Quiz 1easy Behavioral Design Patterns — Part 1 - Template Method pattern - Quiz 3easy Behavioral Design Patterns — Part 2 - Interpreter pattern - Quiz 3easy Behavioral Design Patterns — Part 2 - Visitor pattern - Quiz 1easy Design — Elevator System - State management (idle, moving up, moving down) - Quiz 8hard Design — Library Management System - Reservation and hold system - Quiz 3easy Design — Parking Lot System - Requirements analysis - Quiz 11easy Design — Tic-Tac-Toe Game - Move validation - Quiz 2easy