NBKRIST Java Hub

Problem Statement: Geometric Shapes

Your task is to create a set of Java classes to model different 2D shapes (Square, Rectangle, Triangle) and calculate their area and volume. This problem focuses on applying three key OOP concepts: **Interfaces**, **Abstract Classes**, and **Polymorphism**.

Functional Requirements

• Common Behavior: All shapes must be able to calculate their **area** and **volume**. Since these are 2D shapes, their volume will be 0.
• Shape Types: You must create classes for **Square**, **Rectangle**, and **Triangle**.
• Area Calculation: Each shape must have its own correct area calculation based on its properties (e.g., side for Square, length/width for Rectangle, base/height for Triangle).

Technical Requirements

• Use an Interface:
  • Create an interface, e.g., Measurable, with two methods: double getArea() and double getVolume().
• Use an Abstract Class:
  • Create an abstract class, e.g., Shape, that **implements** the Measurable interface.
  • Inside the Shape class, implement the getVolume() method to simply `return 0.0`. This ensures all 2D shapes have a default volume.
  • The getArea() method in the `Shape` class must be defined as an **abstract method**, forcing all child classes to provide their own unique implementation.
• Concrete Classes (Inheritance):
  • Create three concrete classes: Square, Rectangle, and Triangle.
  • Each of these classes must **extend** the `Shape` abstract class and implement its abstract method, `getArea()`.
• Demonstrate Polymorphism:
  • In your `main` method, create a List of type Shape (or Measurable).
  • Add one object of each concrete shape (`Square`, `Rectangle`, `Triangle`) to this list.
  • Loop through the list and call the `getArea()` and `getVolume()` methods for each object. The correct area calculation will be performed for each shape.

Testing Requirements

Your `main` method must demonstrate the program works by testing the following scenarios:

1. Individual Shape Test:
   • Create a `Square` object with a side length of 5. Print its calculated area (25) and volume (0).
   • Create a `Rectangle` object with a length of 4 and a width of 6. Print its calculated area (24) and volume (0).
   • Create a `Triangle` object with a base of 8 and a height of 5. Print its calculated area (20) and volume (0).
2. Polymorphism Test:
   • Create a List and add the three objects you created above.
   • Write a `for` loop to iterate through the list. Inside the loop, print the area and volume of each shape. The output should show the correct area for each shape in the list, demonstrating dynamic method dispatch.