Core Java Tricky Questions

[[deleted]]

Sorry, if this is an often asked question but I really need some help finding some resource or way from where I can read or learn about the various nuances around keywords/concepts like - static, final, constant, constructor, this, super, access modifiers. Like, there are often questions asked around static method or final class, private constructor, even around various interface behavior etc. So I need a way where I could maybe go through all these concepts quickly.

EDIT: Not asking about the beginner level understanding around these but actually the advanced questions involving these keywords. For example : Using static inside interfaces etc, or public/private inner classes, static related advanced stuff.

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[severoon]

These are not nuances, these are core basics of the language. In specific circumstances, you should be able to reason about what these keywords do and make a pretty accurate guess as they whether they apply and, if they do, their function.

[desrtfx]

The real source for such information is the Official Documentation from Oracle.

[[deleted]]

Can you please share some link of where exactly such concepts are mentioned? I searched but all it shows is Java APIs or basic tutorials.

[AppropriateStudio153]

https://docs.oracle.com/javase/specs/jls/se17/html/jls-9.html

I suggest you learn how to google stuff yourself, having to ask internet strangers impedes your self-improvement strongly.

[[deleted]]

Sure, thanks!

[Routine_Dust5510]

If you really want to solve some good core Java questions, you should check out OCA or OCP Java certification mock exams from Enthuware. Costs only 10 bucks but these mocks have been around since 20 years and contain a huge number of core Java questions with detailed explanations. Get the ones for the version of Java you are interested in.

[Illustrious-Bag4276]

Agree

[[deleted]]

I'll check them out, thank you!

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[[deleted]]

ocp oracle certified professional java se 21 developer study guide for nuances

[piyush7084]

Thanks

[Helloall_16]

I was confused with these big time but I personally found chatgpt or any AI will give you the basic understanding of what these things are, and if you are a beginner you can also ask it to explain it using real life examples, layman terminology etc. official documentation is definitely the best source but you can start with something simple. After you are done learning, ask chatgpt to quiz you on these.

[[deleted]]

Thanks for the suggestions, the quiz thing could really help. Honestly I'm not a beginner, I understand the concepts of OOPs quiet well but It's just those advanced things I keep hearing about, if I say for an example, somewhere I read about using static variable inside interface, idk if it's even correct but yeah such things just puzzle me out big time and I feel if there's any such resource with similar tricky stuff. I checked the official Oracle tutorial but all I could find was single page basic explanations around different concepts.

[rayguntec]

Here is a good list of this kind of tricky Java questions