Classes and Their Relationships: Modeling Real-World Entities and Interactions

In object-oriented programming (OOP), one of the fundamental steps is identifying classes and defining the relationships between them. Classes are used to model real-world entities, while relationships define how these entities interact. This tutorial will explain the process of identifying classes and their relationships, focusing on real-world examples and applying the principles from the previous tutorials on OOP, similar to the Car and Driver example used earlier.

1. Identifying Classes

Classes are blueprints for objects, representing entities in the real world. They encapsulate attributes (data) and methods (behaviors) associated with those entities. The first step in modeling is to identify key entities that need to be represented in your system.

Steps to Identify Classes:

• Look for nouns in the problem description. Nouns often represent entities that can become classes.
• Think about the real-world objects you are dealing with.
• Each class should represent a meaningful entity and should encapsulate all the data and behavior related to that entity.

Example (from the earlier Car-Driver analogy):