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Object-oriented programming (OOP) is a popular method for building new programs. Learn about popular OOP languages and how you can benefit from learning them.
Object-oriented programming (OOP) is a way of thinking about and organizing code for maximum reusability. With this type of programming, a program comprises objects that can interact with the user, other objects, or other programs. This makes programs more efficient and easier to understand.Three of the top five most popular programming languages worldwide in 2022 follow OOP principles [1]. You can learn more about object-oriented programming languages and whether or not they're right for you in the following article.
What is object-oriented programming?
There are four features of object-oriented programmingto know:
1. Encapsulation: Data and methods that interact with that data are bundled into one unit. This allows you to control access to the data within each object.
2. Abstraction: When creating an object, the coder reduces complexity by showing only essential information and "hiding" everything else, including implementation mechanisms.
3. Inheritance: A programmer can derive a new object with all or some of the properties of an existing object. For example, a child class will inherit properties and behaviors from a parent class.
4. Polymorphism: This allows us to use child and parent classes in precisely the same way while maintaining each class's unique attributes.
Object-oriented programming vs. functional programming
Object-oriented and functional programming both aim to develop flexible, easy-to-understand programs while minimizing the possibility of bugs. However, they take two very different approaches. Object-oriented programming languages make it easier to understand how a program works by bringing together data and its behavior (or method) in a single bundle called an “object.”In contrast, functional programming is a model based on performing operations, or functions, on static data. This is based on the idea that data and behavior are different entities and should be kept separate to avoid confusion.
Advantages of object-oriented programming
Programs made with object-oriented programming are well-organized. Since relative data and functions are grouped in the same object, it is simple to find what you're looking for and understand the code's fundamental purpose. Developers new to the project or those revisiting code they have not seen in a while can adapt much faster. When code is divided into manageable pieces this way, you can avoid overwhelmingly large and complicated files. The next few sections take a closer look at some of the advantages of this approach to programming.
Code reusability
Abstraction gives you the ability to reuse code throughout a project. It cuts down on file size and programming work. Knowing you can call a method in a flexible object that already exists means you don't need to rewrite it in another part of the codebase. You can also use self-contained objects in other codebases to speed up development in new projects.
This becomes even more useful if you create a library or framework out of low-level, versatile utility objects. Something like authentication or activity logging would be a useful library, gem, or package (the name differs depending on the chosen language). This allows you to share code with anyone, inside or outside of your project or team. This is how open-source software works.
Testing and debugging
The self-contained nature of object-oriented programming can make testing and debugging easier. It becomes more straightforward to write tests for specific pieces of your project when the objects are only concerned with the functions and data they contain.
Flexibility
Object-oriented programming provides flexibility for your codebase through inheritance and polymorphism. Classes and objects (depending on the language) can also share properties and methods through inheritance. The child class or object inherits everything from its parent. When a child redefines something inherited from a parent, it is polymorphism.
Example: If you have an object called vehicle with a property of number of wheels and a method called drive, then you could create a child object called motorcycle. motorcycle would inherit drive and number of wheels, but you could update number of wheels to have a value of “2." If you ever update the method called drive on the vehicle object, then every child object (like motorcycle, scooter, or bus) would have the new drive method.
Negative side effects of OOP flexibility
Inheritance works for every generation, not just direct parent-child relationships. If you created a child of motorcycle called cruiser, it would inherit everything motorcycle has, as well as every method and property that the vehicle object contains. This feature adds a lot of reusability if you keep your common functions and values in your lower-level objects.
Although this is typically beneficial, it can also lead to issues if you're not careful. You only have to update one function on the parent to update all children, but you may update many children you did not intend to update.
Popular object-oriented programming languages
Several popular programming languages lend themselves to object-oriented programming principles. In each of these languages, it's possible to bundle data and behaviors into individual objects. If you're considering learning an OOP language, here are three of the most common and versatile options to consider:
Java: Java ranks among the oldest and most popular object-oriented languages thanks to its easy learning curve and robust security features. Consider learning Java if you're interested in back-end development, particularly for Android devices.
Read more: What is Java Used For?
Python: Python is easy to learn, easy to read, and versatile; it's an excellent choice for beginners or those who aren't sure what type of coding career they want to pursue.
Read more: What is Python Used For? A Beginner's Guide
C#: C# (pronounced C Sharp) is popular for developing games, desktop, and web applications, particularly on the Microsoft platform.
Read more: C+ vs. Java: Which to Choose?
5 careers that involve OOP languages
Programmers use OOP languages to develop games, mobile apps, and websites. Here are some careers you might consider once you've learned an OOP language:
*All salary data is sourced from Glassdoor as of January 2023. It includes the annual base salary and average additional pay insights such as commissions and profit sharing.
1. Software developer: $95,344
Read more: How to Become a Software Developer: 9 Tips
2. Game developer: $79,830
Read more: What is a Game Developer and How Do I Become One?
3. iOS application developer: $110,051
Read more: What Is an iOS App Developer? A 2023 Guide
4. Android application developer: $102,060
Read more: What Is an Android App Developer? Your 2023 Career Guide
5. Full-stack developer: $86,145
Read more: What is a Full-Stack Developer?
How to learn an object-oriented programming language
Once you've decided which OOP language you want to learn, it can be challenging to know where to start. The list below compiles a couple of online courses from industry leaders and accredited universities. In some cases, you may earn a certificate for your resume upon completion.
Object Oriented Programming in Java Specialization from the University of California San Diego
Crash Course on Python by Google
Object-oriented Design by the University of Alberta
Or, gain hands-on experience and start building your programming portfolio in under two hours with a Guided Project on Coursera:
Intro to Programming With C#: Build A Word Guessing Game
Learn Java with No Prior Programming Experience
Create a Supermarket App Using Java OOP
Get started today with Coursera
Build in-demand development skills by learning a new OOP language at your own pace on Coursera. Learn Object Oriented Programming in Java from Duke University, Python for Everybody from the University of Michigan, or C# Programming for Unity Game Development from the University of Colorado Boulder.
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