What is actually core Java?

[u/Chaos-vy17]

I am literally confused what is meant by Core Java?

• is it JLS?
• is it JVM/JVMs?
• is it OOPs?
• is it understand Collection?

I have become familiar with java. IDK exactly at which phase I am doing. I can do OOPs easily ( have also understood F-form polymorphism) I can easily use stream , collection, iterator API . I can also integrate to them in my project. I started delving into deep JLS, JVMs but after seeing them I am confused are they core java because seeing those topics I felt like I did only basics of java.

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[u/seanprefect]

I don't think there's a formal definition but it would most likely be what you get out of the box with no additional libraries added.

[u/Chaos-vy17 → u/seanprefect]

considering JLS,JVM,JMM are they part of "core java" or they are advanced topic?

[u/seanprefect → u/Chaos-vy17]

if you're talking in an academic context that' depends on the school. When you say JVM if you mean "hey this is the magic black box that makes your code run" that's pretty basic, but the actual way it works is itty advanced. JLS is the language spec, you probably won't ever encounter it unless you decide to build your own version of the JVM, don't worry about Memory Management in the JVM that's not something undergrads deal with.

That said are these very important to make java work? yes very import. But you don't need to know how the engine works to drive a car same with those

[u/Chaos-vy17 → u/seanprefect]

That makes sense. I'm building a data-structure library, so I started reading about the JVM, JLS, and JMM. I guess I'm going beyond what most people mean by "Core Java."

[u/Made-In-Slovakia]

Everything you mentioned is core Java, except OOP because that is abstract concept.

Maybe to understand what is core Java is god to define what is not core Java. In old days it was called Java EE, which contains basically servlets and everything around them, application servers and containers with injections.

Try Google Java SE and Java EE. You can understand Java SE as core Java.

[u/LongIslandThorn → u/Made-In-Slovakia]

User interface libraries are not Core Java even though it's part of the JFK (well, JavaFX wasn't separated into a separate download, but good old Swing is still there). I think of Core Java as the parts of the language every developer is familiar with whether you work on robotics, front end desktop, server side, etc

[u/nitin_is_me]

Haha, even I don't get it. The book Core Java by Cay Horstmann covers a lot more than the points you mentioned. Maybe it's not a formal term or I'm mistaken.

[u/Chaos-vy17 → u/nitin_is_me]

It seems Core Java is much broader than I initially thought. I guess the knowledge and the domain I choose to pursue will determine how deep my understanding of Core Java becomes.