What is object-oriented programming?
Object-oriented programming is a programming paradigm that uses objects and their interactions to design and program applications. It is one of the most popular programming paradigms and is used in many modern programming languages.
The history of object-oriented programming
The first object-oriented programming (OOP) language was Simula67, developed in 1967 by Norwegian researchers Kristen Nygaard and Ole-Johan Dahl. Smalltalk, created in the early 1970s by American computer scientist Alan Kay, is generally considered the first truly object-oriented programming language.
However, it was not until the late 1980s that object-oriented programming languages began to be widely used. The two most popular languages of this era were C++ (developed by Bjarne Stroustrup in 1979), and Smalltalk.
Since then, many other object-oriented languages have been developed, including Java, Python, Ruby, and PHP. OOP is now one of the most popular programming paradigms in use today.
The benefits of object-oriented programming
Object-oriented programming has a number of important benefits. One of the most important is that it makes code easier to maintain. This is because objects are usually self-contained and can be worked on independently of other parts of the code.
Another benefit is that object-oriented code is often more robust than other types of code. This means that it is less likely to contain errors and is more resistant to changes in the environment (such as new operating system versions).
Finally, object-oriented programming can make development faster and easier. This is because objects can be reused in different programs. This means that you don’t have to start from scratch each time you write a new program.
What are the characteristics of object-oriented programming?
In object-oriented programming, the program is organized around objects rather than actions and logic. An object can be a data structure, a function, or a method, and is represented by a self-contained unit of code that has its own data and methods. Object-oriented programming is a coding style designed to make software more modular, scalable, and extensible.
Encapsulation
It is the mechanism that binds together code and the data it manipulates, and keeps both safe from outside interference and misuse. In short, it protects the data, because without encapsulation, the code and data are vulnerable to outside interference.
There are two types of encapsulation in Java – data hiding and bundle classes into a single unit.
Data hiding is about keeping data secret (private) so that unauthorised users cannot directly access or modify it. It is achieved through access modifiers such as private, default (no modifier) and protected.
On the other hand, bundling classes into a single unit (e.g., a .jar file in Java) is also a form of encapsulation because it limits access to only those classes that the users need.
Abstraction
Abstraction is a key characteristic of object oriented programming. Abstraction is the process of hiding the details of an implementation from the outside world. In object oriented programming, this is accomplished by creating objects that expose a well-defined interface, and hiding the details of the implementation behind that interface.
Abstraction allows programmers to develop programs without having to worry about the details of the underlying implementation. This makes development faster and easier, and allows programs to be more reliable and easier to maintain.
Inheritance
Inheritance is a concept in object-oriented programming where a class derives (or inherits) behavior from another class.
When one class inherits from another, the child class automatically has all of the behavior of the parent class. The child class can also have its own unique behavior. Inheritance is a powerful tool that can be used to model real-world relationships between objects.
For example, let’s say you have a base class called Vehicle. This class might have methods for starting the engine, accelerating, and braking.
You could then create subclasses of Vehicle for specific types of vehicles, such as cars, trucks, and motorcycles. These subclasses would inherit the behavior of the Vehicle class, but they could also have their own unique behavior. For example, a car might have a method for honking its horn, while a truck might have a method for dumping its load.
Polymorphism
One of the key characteristics of object-oriented programming is polymorphism, which refers to the ability of different objects to respond to the same message in different ways.
For example, consider a simple shape class that has methods for calculating the area and perimeter of a shape. A square would respond to the area() message by returning its width multiplied by its height, while a circle would return its diameter multiplied by pi. Both objects would return the same value for a perimeter() message, but each would use a different formula to calculate it.
Polymorphism is a powerful technique that allows programmers to write code that is more flexible and easier to maintain. It also makes it possible for programmers to take advantage of code reuse, since objects can share behavior without sharing implementation details.
How is object oriented programming different from other programming paradigms?
In object oriented programming, the focus is on objects rather than on algorithms. These objects can contain data, in the form of fields, and code, in the form of procedures. Objects are created from templates known as classes. Other programming paradigms include functional programming and procedural programming.
Procedural programming
In procedural programming, also known as top-down programming, the program is designed as a sequence of modules, each of which accomplishes a specific task. The interfaces between these modules are typically well defined. The flow of control within the program proceeds from the top (the main module) down to the individual submodules. Data structures may be passed among the modules as needed.
Functional programming
Functional programming is a programming paradigm that is often used in conjunction with object-oriented programming. While the two programming paradigms share some common features, they are fundamentally different.
In object-oriented programming, the focus is on objects and the relations between them. In contrast, functional programming focuses on functions and the relations between them. This difference in focus leads to different approaches to programming.
In object-oriented programming, data is typically represented by objects, and functionality is provided by methods that operate on those objects. In contrast, in functional programming, data is typically represented by functions, and functionality is provided by higher-order functions that operate on other functions.
This difference in approach can be seen in the way that these two paradigms handle state. In object-oriented programming, state is typically managed by objects through their methods. In functional programming, state is typically managed by functions through higher-order functions.
The two paradigms also differ in their approach to inheritance. In object-oriented programming, inheritance is used to define relationships between objects. In functional programming, inheritance is used to define relationships between functions.
Despite these differences, the two paradigms are not mutually exclusive. Many programs use both object-oriented and functional programming techniques.
What are some popular object oriented programming languages?
Object oriented programming is a type of programming where everything is considered an object. This means that every object has its own attributes and methods. Some popular object oriented programming languages are Java, Python, and C#.
Java
Java is a versatile and powerful programming language that enables developers to create robust, high-performance applications. Java is the foundation for practically every type of networked application and is the global standard for developing and delivering mobile applications, games, Web-based content, and enterprise software. With more than 9 million developers worldwide, Java enables you to efficiently develop, deploy and use exciting applications and services.
C++
C++ is a powerful object-oriented language that enables developers to create sophisticated software systems. C++ was created by Bjarne Stroustrup while working on his PhD thesis at Bell Labs in the early 1980s. C++ was designed to be an extension of the programming language C, hence its original name, “C with Classes”.
C++ was released for commercial use in 1985, but it was not yet standardized. In order to standardize the language, a committee was formed and the first international standard for C++ was published in 1998. The most recent standard, known as C++11, was published in 2011.
C++ is a compiled language, which means that it must be converted into machine code before it can be run on a computer. C++ compilers are available for many different operating systems, such as Windows, macOS, and Linux.
C++ is a widely used language in the software industry. It is used to develop desktop applications, such as Microsoft Word and Adobe Photoshop; games, such as Battlefield and Call of Duty; and system software, such as the operating systems for Xbox and PlayStation.
Python
Python is an object-oriented programming language created by Guido van Rossum in the early 1990s. In contrast to other popular languages such as Java and C++, Python adopts a philosophy that emphasizes code readability and a syntax that allows programmers to express concepts in fewer lines of code. Learning Python can be a rewarding experience for beginners and experienced programmers alike.
How can I learn more about object oriented programming?
Online resources
There are a number of online resources that can help you learn more about object oriented programming. One great resource is the Object Oriented Programming wiki, which provides an overview of the main concepts and principles of OOP. Another excellent resource is the online tutorial at Codecademy, which offers a step-by-step introduction to OOP in Python. Finally, for a more in-depth understanding of OOP, we recommend reading “Design Patterns: Elements of Reusable Object-Oriented Software” by the so-called “Gang of Four.”
Books
One way to learn more about object oriented programming is to read books on the subject. Here are a few recommended titles:
-Object Oriented Analysis and Design by Grady Booch
-Design Patterns by the Gang of Four
-Head First Design Patterns by O’Reilly