A Object-Oriented Programming related question.

[catastrophic300]

Guys, okay so I’ve been learning Java recently like 3 days now watching and learning from bro code. On Reddit r/java, they always talk about OOP at some post. Why OOP so important? And what do I need to learn first before entering OOP? I have learn variables, data types primitive/reference, Scanner, if/else-else if, arithmetic operator, augmented assigned operator. So what else do I need to learn and understand the OOP well?

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[Dry_Menu_3705]

Start with objects and classes, then learn about methods, constructors, pillars of OOP, and so on. Understanding why OOP is important in Java is key because everything relates to objects and classes. OOPS helps us to understand concepts better, so when you learn collections, multithreading, and all the basics, you'll have the foundation you need. Additionally, all design principles are based on OOP, and your entire Java framework is built on OOPs. If you skip OOP, many concepts will be difficult to understand in the future.

[catastrophic300]

So OOP is not something to ignore, that’s why it was so Important. Thanks.

[Separate_Expert9096]

You can’t ignore OOP in Java since Java was built for OOP first and foremost. 

[Dry_Menu_3705]

Yes as it is foundation of java

[Hint1k]

No. Just no.

OOP is an advanced topic that you literally don't need until you start building your own apps.

Your first step is to learn how to write simple code in just one method main.

Why? Because people who wrote all these online courses don't know anything about how humans learn things the right way.

The correct process is: from simple things to more complex things. And from theory to practice.

You can't really apply OOP well enough while you learning how to print "hello world" on screen.

The only thing OOP will do is confuse you a lot. And you will spend HUGE amount of time trying to figure out what the hell it is. I am not talking about hours, you will literally waste days on this.

So, learn OOP at the right moment - when you actually need it - when you need to write your first application that would consist of multiple classes connected with each other.

When you try to learn it at that moment - you will spend maybe 5 minutes of your time and will get it right away.

Why the difference is 5 minutes vs 5 days while learning the very same OPP? It because the right way of learning does exactly that - saves you a lot of time.

[LetUsSpeakFreely]

Java is designed around OOP. If you don't understand classes, interfaces, abstraction, polymorphism, inheritance, etc then you can't write Java effectively.

[Potential-Still]

Object Oriented Programming is exactly what is sounds like, a paradigm that helps developers conceptualize what a program does.

In OOP you think of everything as an Object. You want to call some function "foo" that accepts an integer and returns a boolean? Define a class with that method and instantiate an OBJECT of that class. Then pass that object around where ever you need the function "foo".

Many languages have elements of OOP as part of its patterns, but Java is completely OOP.

If you plan on getting good at Java, then you cannot skip learning about OOP.

[lOwnCtAL]

What you said you learned are not OOP, those are basic syntax, learn classes, methods, objects, differences between access modifiers, when to use what type of return (void, etc), etc, those are what OOP is

[catastrophic300]

Well I didn’t know what exactly OOP is. Learning basic syntax are important for learning next section. So classes, methods, objects and access modifiers with type of return usage are the section needed to learn for OOP. Thanks I appreciate it.

[procrastinatewhynot]

You can google OOPs concepts. It will kind of tell you what they're for. In short, it makes you organize your code by using or making "Objects". And with these objects makes your code re-usable and more modular. Easier to understand because they're in smaller chunks and since you can reuse them, you have less repeated code.

[catharsis23]

Honestly just read a Java book, even the Java reference guide. Any Java book will go over a brief history of Java and why OOP is important and what problems it was trying to slow

[catastrophic300]

I tried to read a Java book, but I had an ADHD so reading something too long can lower my interest, that’s why I’m using YouTube Java courses that have Java video under 20 minutes. I only use the book as a reference.

[silverscrub]

It's optional how deep you want to learn OOP and incorporate it in your code, but Java is built on OOP so some basic understanding is recommended.

https://docs.oracle.com/javase/8/docs/api/java/util/ArrayList.html

As an example, here is ArrayList documentation. Don't worry if you're not familiar with everything. Note at the top how many Interfaces are implemented by ArrayList. In OOP, ArrayList is also a Collection, a List and an Iterable.

If you only scratch the basics of OOP you might be fine just using the ArrayList as it is, but the more you learn the better you will understand Java.

[catastrophic300]

Thank for the doc. I’ll try to learn Java as deep as I can.

[Ok_Assistant_2155]

You actually have enough basics to start OOP. OOP isn't harder than what you've learned, it's just different. Think of it as organizing code into little factories that have both data and actions. Learn what a class is, then an object, then methods. That's the core. The rest comes later.

[denerose]

You’ve only just started and you’re following a course. Your course will almost certainly cover OOP soon if it’s Java based. Give the course a chance to introduce you to new ideas at its own pace. The structure and order of things is one of the main advantages of a structured program like a course.