What are Abstract Methods?

An abstract method is a method that is declared without an implementation. It is a blueprint for a method that must be implemented in a subclass. Abstract methods are used to define common functionality for a set of related classes.

Examples:

1. Animal Class:

   • Abstract Class: Animal
   • Abstract Methods:
     • makeSound()
     • move()

   Subclasses:

   • Dog:
     • makeSound() might return "Woof!" and move() could describe how a dog walks or runs.
   • Cat:
     • makeSound() might return "Meow!" and move() could describe how a cat prowls or jumps.
   • Horse:
     • makeSound() might return "Neigh!" and move() could describe how a horse gallops.

2. Shape Class:

   • Abstract Class: Shape
   • Abstract Methods:
     • calculateArea()
     • calculatePerimeter()

   Subclasses:

   • Circle:
     • calculateArea() could use the formula for the area of a circle, and calculatePerimeter() could use the formula for the circumference.
   • Rectangle:
     • calculateArea() might be the product of its length and width, and calculatePerimeter() could be the sum of all four sides.
   • Triangle:
     • calculateArea() might use the formula for the area of a triangle, and calculatePerimeter() could be the sum of its three sides.

3. Employee Class:

   • Abstract Class: Employee
   • Abstract Methods:
     • calculateSalary()
     • displayInfo()

   Subclasses:

   • Manager:
     • calculateSalary() could use the manager's base salary plus bonuses, and displayInfo() might show their management responsibilities and contact details.
   • Developer:
     • calculateSalary() might be based on the developer's hourly rate and hours worked, and displayInfo() could include their programming skills and projects.
   • Salesperson:
     • calculateSalary() might involve a base salary plus commissions, and displayInfo() would include their sales achievements and territories.