Class responsibilities and behavior in LLD - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the primary responsibility of a class in object-oriented design?

A class is responsible for managing its own data and behavior. It encapsulates related properties (attributes) and functions (methods) that operate on that data.

beginner

Explain the term 'behavior' in the context of a class.

Behavior refers to the actions or methods a class can perform. These methods define how the class interacts with data and other objects.

intermediate

Why is it important for a class to have a single responsibility?

Having a single responsibility makes a class easier to understand, maintain, and test. It reduces complexity by focusing on one clear purpose.

intermediate

How does encapsulation relate to class responsibilities?

Encapsulation means hiding the internal details of a class and exposing only what is necessary. This protects the class data and ensures it controls its own behavior.

beginner

Give an example of a class responsibility in a real-life system.

In a banking system, an Account class might have the responsibility to manage the balance, process deposits, and handle withdrawals.

What does a class primarily encapsulate?

A User interface

B Only data

C Only behavior

D Data and behavior

A class encapsulates both data (attributes) and behavior (methods) that operate on that data.

Why should a class have a single responsibility?

A To make it easier to maintain and understand

B To increase complexity

C To handle multiple unrelated tasks

D To avoid using methods

Single responsibility helps keep the class focused, making it easier to maintain and understand.

Which of the following best describes 'behavior' of a class?

A The class name

B The data it stores

C The methods it can perform

D The file where it is saved

Behavior refers to the methods or actions a class can perform.

Encapsulation in a class means:

A Hiding internal details and exposing only necessary parts

B Making all data public

C Writing all code in one method

D Ignoring data protection

Encapsulation protects data by hiding internal details and exposing only what is needed.

Which is an example of a class responsibility?

A Designing the website layout

B Managing user login in a User class

C Sending emails from the server

D Storing images on disk

Managing user login is a clear responsibility of a User class.

Describe what is meant by class responsibilities and how they relate to behavior.

Think about what a class 'owns' and what it 'does'.

Explain why single responsibility is important for class design and give a simple example.

Imagine a class trying to do too many unrelated things.