Object-oriented Model

Introduction

The object-oriented model is a type of software design and programming paradigm that uses "objects" to design applications and computer programs. These objects are instances of classes, which are essentially user-defined data types. The object-oriented model is characterized by four main principles: encapsulation, inheritance, polymorphism, and abstraction.

A computer screen with lines of code, representing object-oriented programming.

Principles of Object-Oriented Model

Encapsulation

Encapsulation is the bundling of data, along with the methods that operate on that data, into a single unit. In an object-oriented model, a class defines the properties and methods that will be common to all objects of that class. Each object of a class will have its own copy of the data, and access to it is controlled by the methods defined within the class.

Inheritance

Inheritance is a mechanism that allows one class to acquire the properties and methods of another class. The class being inherited from is known as the superclass or parent class, and the class that inherits from the superclass is known as the subclass or child class. Inheritance promotes code reusability and hierarchical classification.

Polymorphism

Polymorphism is the ability of an object to take on many forms. The most common use of polymorphism in object-oriented programming occurs when a parent class reference is used to refer to a child class object. Polymorphism allows routines to use variables of different types at different times.

Abstraction

Abstraction is the process of hiding the complex details of an object and exposing only the essential features of the object. Abstraction helps to reduce complexity and isolate the impact of changes in the code.

Advantages and Disadvantages of Object-Oriented Model

The object-oriented model has several advantages over other design approaches. It promotes greater flexibility through polymorphism, and code reusability through inheritance. Encapsulation provides a way of bundling data and methods into a single unit, improving security and simplicity. Abstraction allows for complexity to be hidden, making the system easier to manage.

However, the object-oriented model also has some disadvantages. It can be more complex to design and implement than procedural programming models. It can also be less efficient in terms of memory and processing power, as objects are larger and slower than procedural routines.