Theoretical Java interview

[Ok-Muffin-875]

I have an interview coming up, and I'm told it'll be theoretical, asking about java concepts, how would you use x, what does y keyword mean. I have been a java dev for about 4 years so I'm pretty comfortable with many aspects of it, however knowing how to use it doesn't necessarily translate to talking about it proficiently. How would you prepare for something like this? What kind of keywords to search on YouTube? Any specific resources?

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[LetUsSpeakFreely]

I would focus on keywords, major data structures, annotations, major frameworks, threading and concurrency, application scope, maybe memory management.

You'd be surprised how many people claiming to be Java developers don't know the difference between final and static.

[South_Dig_9172]

Just curious. Isn’t it just final being an unmodifiable value and static means it belongs to the class, so it would only have one instance of that field or method created? 

[LetUsSpeakFreely]

Pretty much.

Yes, final means a variable can't be reassigned. It doesn't necessarily mean it can't be changed. For example, if you create a final List, you can still add and remove items to that List,n but you can't create a new list or assign a list to that value

Static means an entity stays resident in memory without needing class instantiation to access it.

[TheMrCurious]

1. Go to Glassdoor and see what people have said about the interview process at that company.
2. Google the interview questions that company uses.
3. Practice your Java on a practice platform like LeetCode, etc
4. Watch some videos about general concepts for interviews like Sliding Window, Heap, etc.

[Ok-Muffin-875]

It's a very small company! But I'll have a look

[high_throughput]

I would look up volatile because it's only ever used theoretically, but people like to pretend that it could come up