Object Oriented Programming (OOP)
You’ve probably seen most back-end programming languages described as object-oriented programming (OOP)—so what is object-orientation in web development, and why is it important?
At its core, it’s a logic—one we use in daily life. We naturally think of things as objects with attributes and behaviors, and that determines how we interact with them. It’s interacting in the abstract, and it’s why OOP can boost speed and efficiency.
What is abstract interaction?
If you want to change the television channel from your seat, you use a remote control. That remote control is an object with a number of attributes and behaviors hidden inside of it. Without an understanding of those hidden attributes—the microchips, wiring, etc.—you still know and expect that pressing a button will perform that particular function. You’ve interacted with the remote control in the abstract, skipping the steps the remote was designed to carry out. That’s the beauty of OOP—the focus is on how the objects behave, not the code required to tell them how to behave.
So, what are objects?
A car is an example of a complex object, with many attributes. We don’t need to understand all of its internal mechanics, what kind of engine it has, how the gas makes it run, or even where the gas came from in order to know how to interact with it. The car’s behaviors have been made simple for us through object-oriented logic: put the key in the ignition, and the car turns on and gets us where we need to go. The attributes that make this possible—all of the car’s parts, electronics, and engineering—are a “package” we don’t need to break down in order to understand.
Apply this to software building, and it allows developers to break down big, complicated projects into compartmentalized objects, program them to have attributes and behaviors, then essentially set them aside and focus on programming how the objects interact—a higher level of thinking that makes writing code less linear and more efficient. Modern, high-level languages like Python and Ruby are perfect examples of OOP. The fact that they’re able to be so streamlined gets right to the heart of OOP logic.
Object-oriented programming & back-end development
What is object-oriented programming in terms of how a site is built? OOP defines most modern server-side scripting languages, which are the languages back-end developers use to write software and database technology. This behind-the-scenes, server-side technology tells a website or web application how to behave, and also builds the architecture for a site to interact with its database. That scaffolding is how data is delivered and processed, effectively making it the brain of a website. And that’s where object-oriented logic comes into play.
If a website’s brain uses object-oriented logic, it’s designed to think of data as objects. It affects how a site is built from the ground up, how data is organized, how later growth and maintenance of the site will occur, and more.
Benefits of object-oriented technology include:
- Ease of software design
- Productivity
- Easy testing, debugging, and maintenance
- It’s reusable
- More thorough data analysis, less development time, and more accurate coding, thanks to OOP’s inheritance method
- Data is safe and secure, with less data corruption, thanks to hiding and abstraction
- It’s sharable (classes are reusable and can be distributed to other networks)
The building blocks of object-oriented programming
Objects are central to OOP, but they’re not the only moving part. Here’s a closer look at the other building blocks, and how they work in tandem to create back-end code that houses, moves, and manipulates data from a database into a usable web application.
- Objects: An object is the core unit of OOP. Objects are uniquely named and represent an instance of a class. Each object houses different states (attributes), and shared behaviors, called methods. For example, a Prius is an object in the class of “cars,” in a subclass of “hybrid cars.” Its attributes include anything from the number of doors it has to how its electric component is charged. It’s similar to other cars by its behavior—it drives—but its attributes are what set it apart.
- Classes: A class is a blueprint for how an object is built, as well as being a sort of “parent category” for objects. Using the previous example, a class dictates the concept of a car—four wheels, an engine, a body, brakes, etc. It allows certain set criteria to be passed down to all objects in the class. All varieties of cars behave relatively the same on a basic level, but its their attributes and methods that make them unique.
- Inheritance: This is an important aspect of OOP, hinted at above. By deriving classes from parent classes, behaviors can be passed down to objects, then more complicated attributes can be added the deeper you go. For example, breaking a car into subclasses (car → sports car → V8 sports car) makes it possible to layer in more features without starting from scratch.
- Abstraction & Encapsulation: This describes how attributes are housed and hidden within an object—including its data. Objects are designed to only reveal the necessary data, allowing software to interact with the object on a higher level. It’s equal parts security and simplicity. In the case of car parts, by safely stowing them within the body of an assembled car, things are less likely to get broken, and users can interact with the big picture: pressing the gas means go, no questions asked.
Procedural languages vs. object-oriented languages
Procedural programming (via languages like ColdFusion) is code that is broken into “procedures”—it’s a different way of thinking about how code interacts with data that’s more linear. Procedures are functional bits of code that interact with and change data, like little machines that gather input, process it, then deliver output. With OOP, however, data and functions (attributes and methods) are bundled together within the object. This prevents the need for any shared or global data with OOP, which is a core difference between the two approaches.
Traditional procedural languages like C and Pascal require you to think in terms of the computer rather than thinking in terms of the problem you’re trying to solve. For less complicated applications, procedural languages offer ease and transparency that bundled objects don’t always allow—something that can make it more difficult for programmers to analyze smaller bits of code on the tail-end of the development process.
When it comes to creating reusable components in software, OOP is the clear winner. Reusability leads to efficiency, simplifying programming and creating “shortcuts” to software design.
Popular object-oriented languages
- Simula, the first object-oriented programming language
- Java
- Python
- Ruby
- C++
- Smalltalk
- Visual Basic .NET
- Objective-C: OOP is a core tenet of iOS mobile app programming, and Objective-C is essentially the C language with an object-oriented layer.
- Curl
- Delphi
- Eiffel