Challenges we face while making the transition from Procedural Programming to OOP

While working on this blog — Fundamentals of OOP s in Java— we came across a LinkedIn post where people were sharing their thoughts on the challenges developers face when moving from procedural programming to object-oriented programming (OOP). The comments were really interesting and gave us a lot to think about. Many of the points we’re covering in this blog are based on those discussions, but a more detailed version. We hope you enjoy reading it!

Whenever we try to move from one topic to another — especially something very different from what we already know — it can feel confusing at first. It’s normal to struggle, especially when we are learning something completely new. That’s exactly what happens when developers shift from procedural programming (like writing step-by-step code) to OOP, where the approach and thinking style are quite different.

So in this blog, let’s talk about some of the common challenges developers face when making this switch. These struggles are not really about any specific programming language as OOP works in languages like C++, Java, Python, and many others, but for simplicity we have chosen the Java language.

Let’s get started!

Conceptual Shift

As told above, the learning curve of OOPS is very different from the learning curve of Procedural Programming. It is more like an S shape graph rather than a straight line. At first it is very hard to understand concepts like abstraction, polymorphism, inheritance, etc.

Before that we have to first change the way we think and approach problems. Procedural programming is all about writing codes in terms of functions and processing data step by step, but OOPS is like a different world altogether like an alien planet where we have to learn and adjust everything from scratch.

Here everything is made up of objects, we have to keep our data secure and hidden using techniques like abstraction and encapsulation.

How to write code in such a way that it can be used again and again and in different forms (next level dynamic coding) using polymorphism. This is not an easy task and requires not only a different mindset and approach but also regular practice as told above.

In procedural programming, we write our codes in the following way

public class Main {
 
    public static void main(String[] args) {
        drive(); // Call the static method
    }
 
    static void drive() {
        System.out.println("The car is moving");
    }
 
}

Output

But now that same code will look something like this

class Car {
    void drive() {
        System.out.println("The car is moving");
    }
}
 
public class Main {
    public static void main(String[] args) {
        Car myCar = new Car();
        myCar.drive();         
    }
}

Now this shift is huge. This is the shift that we are talking about, it’s not only conceptual but also noticeable.

Understanding Classes

In Object-Oriented Programming (OOP), classes play a foundational role. At their core, classes act as a blueprint that is used to create an object, as it tells us which properties and methods the object will have.

However, a class by itself doesn’t produce any output when the program runs — only when an object is created from it and its methods are used does the code become functional.

This concept can be confusing, especially for those transitioning from procedural programming, where writing code and immediately seeing output is the norm. In contrast, OOPs require organizing code into reusable and modular components, which involves a shift in both design and thinking.

Classes help implement the four main principles of OOP: encapsulation, inheritance, polymorphism, and abstraction. These principles make code more modular, maintainable, and scalable while hiding complex details to improve security. And finally relationships like “is-a” (inheritance) and “has-a” (composition) can be pretty confusing and challenging.

Mastering Syntax

In the above section we wrote a code that tells exactly how much difference there is between the syntax of a normal java code and code written using OOPS principles, they are leaps apart. Like in normal Java code, we don’t have to think about classes, objects and other stuff.

Rather it is only about the task that we have to perform. But here, we have to think about classes first even before creating objects as they will be created from these classes only.

The syntax of the OOP program does not change only because of the presence of classes and objects, it changes with slight modification in our main method. The main method as we all know is the starting point of every Java program and the starting point of OOPS as well.

The main method is static in nature and is present even in simple Java programs, but what makes a program truly object-oriented is not the presence of a class, but how objects are created and used within it.

Main Method in a Simple Java Program

public class SimpleProgram {
    public static void main(String[] args) {
        System.out.println("Hello, world!");
    }
}

Main Method in an Object-Oriented Java Program

public class Main {
    public static void main(String[] args) {
        Car myCar = new Car();     // Object created
        myCar.drive();             // Object method called
    }
}

The main method is just the starting, there are concepts like the constructors and methods which syntax wise looks the same but are not, constructors do not have a return type while methods do.

And finally the access modifiers which define the visibility and accessibility of a class can confuse us as which specifier to use under which conditions or circumstances as there are four of them.

Conclusion

So in the end, we can say that moving from procedural programming to object-oriented programming isn’t always easy. It involves a shift in mindset, new concepts to understand, and sometimes even syntax changes.

On top of that, the learning curve for OOP isn’t smooth or simple. It looks something like this:

1. Initial steep climb — Grasping the core concepts like classes, objects, and encapsulation.
2. Flatter middle — Becoming comfortable with writing basic OOP code and structuring programs.
3. Bumps along the way — Learning more advanced ideas like inheritance, polymorphism, and design patterns, which build on earlier concepts.

Understanding that this journey takes time can make it easier to stick with it. With practice, things start to fall into place, and OOP becomes a powerful tool for writing better, more maintainable code.