All Flashcards
What is the main purpose of a class in Java?
To define the structure and behavior of objects.
Why are instance variables often declared as private?
To enforce encapsulation and protect data integrity.
What is the role of a constructor in object creation?
To initialize the object's state by assigning initial values to its instance variables.
How does encapsulation contribute to code maintainability?
By hiding internal implementation details and preventing unintended modifications from outside the class.
What is the significance of the 'new' keyword in Java?
It is used to create a new instance (object) of a class.
Explain the concept of information hiding.
Restricting access to certain components of a class to prevent improper access or modification.
What is the purpose of a getter method?
A method used to access the value of a private instance variable.
What is the purpose of a setter method?
A method used to modify the value of a private instance variable.
What is the role of the main method?
It is the entry point for the program.
What are the three main parts of a class?
Variable declarations, constructors, and methods.
How are classes used in designing a banking system?
Classes can represent entities like accounts, customers, and transactions, each with specific attributes and behaviors.
How are classes used in developing a game?
Classes can represent game objects like players, enemies, and items, each with their own properties and actions.
How are classes used in creating a graphical user interface (GUI)?
Classes can represent GUI components like buttons, text fields, and windows, each with specific properties and event handlers.
How are classes used in managing data in a database?
Classes can represent database tables and records, each with specific fields and methods for data manipulation.
How is encapsulation applied in real-world scenarios?
Protecting sensitive information in a user profile by making attributes private and providing controlled access through methods.
How are classes used in designing a library management system?
Classes can represent books, members, and librarians, each with specific attributes and behaviors related to borrowing and returning books.
How are classes used in developing an e-commerce platform?
Classes can represent products, customers, orders, and shopping carts, each with specific attributes and methods for managing products and processing orders.
How are classes used in creating a social media application?
Classes can represent users, posts, comments, and messages, each with specific attributes and methods for creating and sharing content.
How are classes used in managing student records in a school?
Classes can represent students, courses, teachers, and grades, each with specific attributes and methods for managing student information and academic performance.
How are classes used in designing a flight booking system?
Classes can represent flights, passengers, bookings, and airports, each with specific attributes and methods for managing flight schedules and booking reservations.
What is a class?
A blueprint for creating objects, defining their attributes and behaviors.
What are instance variables?
Variables that characterize objects within a class.
What is a constructor?
A special method used to create objects of a class.
What is a method?
A function associated with an object, defining its behavior.
What is encapsulation?
Bundling of data and methods that operate on that data, and restricting access from outside.
What is a client in the context of a class?
Other users and classes that interact with a class and its objects.
What is a class header?
The first line of a class definition, specifying the class name and visibility.
What is a class body?
The code block enclosed in curly braces that contains variable declarations and methods.
What is a default constructor?
A constructor with no parameters, providing default values for instance variables.
What is an overloaded constructor?
A constructor with the same name as another constructor but with different parameters.