Object Oriented Programming

What is the main principle of object-oriented programming?

• Inheritance of properties from a parent class.

• Polymorphism through method overloading.

• Encapsulation of data and behavior into objects.

• Static typing of all variables in the program.

Define a class in the context of OOP.

• A class is a type of variable used in programming.

• A class is a function that executes code.

• A class is a collection of data without any methods.

• A class is a blueprint for creating objects that defines attributes and methods.

What is an object in object-oriented programming?

• An object is a function that performs actions.

• An object is an instance of a class that contains data and methods.

• An object is a type of variable that cannot hold data.

• A class is a blueprint for creating objects.

Explain the concept of inheritance in OOP.

• Inheritance is a method for creating new classes without any relationship to existing ones.

• Inheritance allows a subclass to inherit attributes and methods from a superclass, promoting code reuse and establishing a class hierarchy.

• Inheritance is a way to delete attributes and methods from a superclass.

• Inheritance allows a subclass to override all methods of its superclass without any restrictions.

What is polymorphism and how is it used in OOP?

• Polymorphism is a design pattern used for database management.

• Polymorphism restricts objects to a single class type in OOP.

• Polymorphism is a method of data encryption in programming.

• Polymorphism allows objects of different classes to be treated as instances of a common superclass, enabling method overriding and interface implementation in OOP.

Describe encapsulation and its importance in OOP.

• Encapsulation allows unrestricted access to all class components.

• Encapsulation is only relevant in procedural programming, not OOP.

• Encapsulation is the process of separating data from methods in OOP.

• Encapsulation is the practice of bundling the data (attributes) and methods (functions) that operate on the data into a single unit or class, while restricting access to some of the object's components.

What is the difference between an abstract class and an interface?

• An abstract class can have multiple inheritance, while an interface cannot have any inheritance.

• An abstract class can have implemented methods and state, while an interface cannot have implemented methods (except default methods) and cannot maintain state.

• An abstract class cannot have any methods, while an interface can have multiple implemented methods.

• An abstract class can only be instantiated, while an interface cannot be instantiated at all.

How does method overloading differ from method overriding?

• Method overloading is used for private methods only; method overriding is for public methods.

• Method overloading is about having the same method name with different signatures; method overriding is about redefining a method in a subclass.

• Method overloading requires different method names; method overriding does not.

• Method overloading allows changing the return type; method overriding does not allow this.

What role do constructors play in a class?

• Constructors initialize objects and set up their initial state.

• Constructors are responsible for handling exceptions in a class.

• Constructors define the methods of a class.

• Constructors are used to delete objects from memory.

Can you explain the concept of a destructor in OOP?

• A destructor is a function that creates new objects.

• A destructor is a member function that is invoked when an object is destroyed, used to release resources.

• A destructor is a type of variable that holds data.

• A destructor is used to initialize an object when it is created.