Array vs. ArrayList in Java Tutorial - What's The Difference?

Arrays vs. ArrayLists - What's the difference? How do you use each of them, and which one should you use and why?

We'll go in-depth about the similarities and differences between Array and ArrayList in Java, and talk about how to create them, add elements, remove elements, and more.

This is a beginner friendly beginner's Java coding lesson tutorial, where we'll talk all about using Arrays and ArrayLists.

Learn or improve your Java by watching it being coded live!

Hey, I'm John! I'm a Lead Java Software Engineer who has been in the industry for over a decade. I love sharing what I've learned over the years in a way that's understandable.

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[whatisahandleeee]

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[aligmayu]

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[kerwinso]

You explain diamond operators (starting at 4:19) in 20 seconds better than others who have taken over 5 minutes. Well done sir.

[sanabil]

you are going to have million subscribers one day, already telling ya, you teach so well :)

[HuwJones]

Great video. Two things....it's considered good practice to use the interface on the left side so List<String> instead of ArrayList<String> before the variable name. And while you are right that the ArrayList itself can grow and shrink it's really important to be aware that the array that backs the ArrayList (yes there's an array hiding inside the ArrayList implementation!) does not shrink automatically after the ArrayList has grown...this can be very significant when profiling the memory footprint of an application. Lastly, it would be really good to have a video on why you'd pick a primitive representation over its Object memory usage, etc.

[lootster]

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[mkn]

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[anityyu]

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[filipemelo]

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[oldschoolmath]

Thanks so much for sharing this video! We watched this in my AP CS A course after finishing a unit on Arrays and you did a great job of giving us an intro to ArrayLists.

[carlosgranda]

Dude, I swear to God how can you explain so well that I didn't get distracted. bro when my teachers explain I lose focus so fast, dude keep it going you are amazing.

[robertjr]

Watching your videos helps me understand so much better. You explain everything perfectly and add in the little important details that most books or instructors seem to not mention,

Thank you!

[JACINTADOITA]

My Exam is on Monday and my teacher did not cover this topic on JAVA. By watching this video I'm prepared for my Exam, thanks very much.

[bbalmer]

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and i got just a nice ass dopamine hit, thank you.

[thecolorblue]

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[sajidamoin]

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[fridolinmeier]

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[mastermatt]

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[aces]

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