LinkedList vs ArrayList in Java Tutorial - Which Should You Use?

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Updated answer: Although the complexity analysis in this video still stands, in real world applications, ArrayList is the better choice for virtually every single use case. See the pinned comment below for more info.
LinkedLists are a great data structure to be familiar with, but they can be confusing. If you're familiar with ArrayLists in Java and how to use them, then LinkedLists can be used in the same way.
But when should you use a LinkedList vs. an ArrayList? How do you use them - are there any differences. We'll go over all of that and more in this beginner/intermediate Java video tutorial lesson.
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[@prototype0277]

I've been working with Java for nearly 15 years now. I remember studying linked list in and various other data structures in college. John, you explained something that college professors flunked folks over so much better and in a matter of minutes rather than days. Bravo sir.

[@findlestick]

Your channel is the only one that has increased my enthusiasm for Java, tenfold. Your videos really are a breath of fresh air here on KZbin. I’m going to watch all your vids and thumb-them-up in gratitude. 👍

[@CodingWithJohn]

Awesome, I'm really glad I could inspire that kind of interest!

[@usernameusernameusername9835]

I love your videos!

[@MarkSmith-vo1vn]

@@CodingWithJohn Could you do a Hashset video by chance.

[@CodingWithJohn]

Great idea! I'm actually planning that for my very next video.

[@pequetreques]

I was about to post this: "Many tutorials here on KZbin, and on Udemy, etc. But this is the very first time I feel utterly comfortable with one of them, because you go straight to the point in a very clear way, avoiding extra explanations. Thanks for your time/work!". But @findlestick already put a good one, so mine replying his. Thanks again John, you definitely rule this thing. ❤

[@jam-yh9il]

I don't know how your videos can be so condensed but still thorough. Thanks from all of the Computer Science majors.

[@alexanderrizzi8003]

This is *by far* the easiest video to help understand this concept. As a relatively new programmer, I always found it somewhat puzzling to have different implementations of the List interface, but this video clears so many things up and gives actual reasons for their existence! Cheers!

[@goerekt]

I once had a job to improve performance of a java application. Best improvement was done by just exchange a LinkedList to an ArrayList, because it was used to read a lot by index. Very simple change, but massive impact.

[@DassVeryGood]

Crazy how someone can explain all this clearly and simply in 10 minutes. Where my uni would take 2 mins of explaining nothing with a minimalistic slide showing what a linked list looks like. Thank you so much

[@Daniel95221]

This is like my operating systems course but condensed in the best way. Thanks for the videos! ❤️

[@gabenixon6141]

July 14, 2022 - Properly learned ArrayList and LinkedList. Thanks John!

[@lootster]

I have problems understanding LinkedList despite reading numerous articles online. Your video is a god's gift!

[@nerminkarapandzic5176]

I just found your channel, this is the second video I'm watching and it has already become my new favorite channel. Good work, keep it up :)

[@paulaa5210]

Thank you so much for all these videos! I've been watching them this semester and they have helped tremendously

[@Lyosha.]

The arrayList does not leave a "space" for the new element in the new array. It instead duplicates all the values from the index into which you want to move the new element into . Those duplicates are positioned one index down from that point (you get one doubled item ) and then that doubled item is replaced with the new one you are moving so the process it's actually longer than what you explained :)

[@briangitego]

These are the best Java tutorials that I've found on KZbin and believe me I've looked. Thanks a lot really!!

[@MrCosmonaut]

I'm glad youtube suggested me your channel John. Your videos are truly inspiring, and quite useful for a beginner like me. I want to declare my appreciation for the work you're doing here =) Thank you!

[@jerryg2757]

You’re great man. Love your enthusiasm for Java. Keep it up!

[@muradalnajjar6533]

Thank you very much, John! Your way of explaining java concepts is very straightforward to understand. Your videos are worth every second to watch.

[@alicewu6674]

this is the only video that really makes me understand what an arraylist and linkedlist is, thank you!

[@slaki1706]

Amazingly clear video, great job. Just a minor remark: To emphasize that the interface of the two lists is the same you could have used just List as their type. Generally, that is the recommended way anyway.

[@l19870922]

Hi John. Thank you for your wonderful clarification. This is by far the most clear tutorial I have ever watched to understand the difference LinkedList vs ArrayList and you explained it in a perfect way so that I could easily understand it without even re-watch the video.

[@bekbolots9634]

How can a man be so precise with his teaching! Great job.

[@ayushgupta8239]

Wish i had someone to teach me these stuff earlier…I had to learn these things the hard way. Awesome video man!! Just one thing I think array list uses a load factor of (0.75) to decide when to scale up not when the list is totally full(e.g. like reached 10)

[@denniskim4326]

Thank you for your videos. Trying to learn Java on the job and your tutorials are quite literally saving me at every turn.

[@YushinWE]

Wow. What an easy-to-understand yet well-informed video. This is much better than my professor's two-hour lecture on this subject. This is exactly what I want to watch for learning anything!

[@davishilton4754]

You explain things so clearly, keep up the good work and Thanks!!!

[@ginandi1]

In most use cases, amortized analysis shows equivalence of run time. Linked lists, however, lead to more cache misses (array can be bulk copied to cache with much fewer misses) which puts array in a huge advantage for practical reasons as well.

[@franfonse]

John. I'm computer engineer student, and your videos are just brilliant. Thank you so much for so, so good content. Keep it up! I will support this channel the best way I can :-)

[@jeeperscreepers7]

Love your videos! been watching all of them to get prepared for my next job interview :P

[@emiliasavin6484]

Love your videos, short and informative 👍

[@omarnoor4249]

Thanks for your tutorial they are helping me a lot in my Java studies. You are a genius.

[@wickedsnuk3812]

It was like those lectures where the instructor teaches so smoothly so s/he puts everything in your mind without you noticing.

[@Hugos68]

Thank you for the comprehensive video with plenty of examples and thorough explanation!

[@antonsilta7248]

Thanks a lot, barely could be clearer! Interesting as hell, can't stop watching :)

[@aco7992]

Thanks for clear explanations. I exactly found out what I am looking for.

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Hey John. I was cording for past 10 years. Never ever thought about it. You are an eye opener. Wonderful explanation. Thank youuuuuu veryyyyyyy muchhhhh😄😄😄😄😄👍👍👍👍👍

[@markbozinovic706]

Thanks John, good starting point for Java Coders in the intermediate stages looking to go advanced and being Java is applicable with mobile apps. Have posted on my twitter, Regards and keep these videos going. Mark

[@erezswickley2139]

Finally, a clear explanation, Thank you! You definitely earned my subscription.

[@will_smith_0073]

You make very understandable videos, keep it up!

[@amirulidzham]

I learn java since 2014 but now I understand it. Huge thanks

[@Hackers16]

thank you so much for this tutorial. now I know what is really the difference between them. I hope you’ll grow your channel more. Please make a tutorial for Data Structures in Java as well. That would be really helpful

[@globalskills2861]

Hey John i am from morroco nord of Africa i am beginer in Java i just want to Say you are doing a great work your vidéos helps a lot .

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Dude, I love your channel, I hated Java a time ago but I've been working with php (some POO) and I've been opening my mind to Java too, I had to do a Project using Java to my College last month, and you helped me so much with your videos. Now I'm watching every video just because I started to Love it. Thanks Bro! Ps: I'm from Brasil, and my english isn't that good.

[@newaccaunt6648]

Thank you very much. Quality of the lesson is really good. You are professional. Keep it doing! 👍👍👍

[@aldotube88]

First time watching your videos, very good explanation at helping me understand this!

[@SpooxyCowboy1911]

It’s so refreshing to hear an explanation that doesn’t have a heavy accent. Almost all my professors are hard to understand and it makes it difficult to learn

[@muhammed__5]

Really love it ur videos John!

[@UmangMundhara]

Really appreciate your explanation , it was too clear and these concepts are pretty clear to me now

[@kaledbrahmi3442]

Thank you, I was struggling to understand the difference and now is all clear. Btw I like your channel and I wish you to grow because you deserve it.

[@CodingWithJohn]

No problem at all. Thanks for the kind words, and thanks for watching!

[@theblindprogrammer]

ArrayList is really heavily used in Android as well.

[@IbytheGOAT]

I make sure to search your name for any Java concept I gotta learn, you explain things perfectly

[@Nitrev]

Im new to Java and started self-studying. This is so easy to understand thank you

[@Jtube0101Mega]

Great lesson! Thank you very much!

[@asherkhan2656]

Great explanation and good review for me…thank you

[@marionthenault8670]

This is so clear and so helpful, thank you

[@Leandro-zo4kp]

Thank you very much for the content!! Your teaching is great!! Gratitude

[@dypsking3414]

Super clean & neat explanation 💕

[@joannecarrig384]

Thank you so much. Your videos are great and really easy to understand.

[@JbizzyLoL]

Just want to show appreciation for these videos. You're saving me from drowning in my programming & methodologies II course!!

[@onkarjadhav4186]

I have watched lots of video for understanding ArrayList and LinkedList difference but this video fix my all doubts.

[@balag3611]

Ur explanation way are such incredible.Thank you bro . Definitely your channel will 1M subscribtion in the future....Can u say what type IDE r u using

[@sarahjuliana7683]

John, you are awesome. Thank you for your work !

[@koksalocal7153]

Thank you john for your precious informations and waiting for the next ones😊

[@darthnihiluz5305]

As of late I've been getting into Java functional/lambda/reactive programming. Definitely took a little bit to get use to, maybe do a series on it?

[@sardorruziyev6919]

Thank you John, very much appreciated!

[@panditfamily4202]

Superbly explained 😍....just awesome 👍

[@HarshSharma-pk6co]

Thank you so much for explanation, i am us array list most of time. But i had read it multiple time but didn't understood it well. But in your end of the video when you gave example that made me understood. Now i know which to use when

[@dd8601]

Great explanation.thank you so much

[@fcbarcatv-ou4ww]

i have so much respect for you good sir. you are carrying my revisions

[@philippecourtemanche7667]

great explanation Thanks John

[@mahmad9095]

Thanks for the awesome video. I had bought some Java course on Udemy and I keep coming to your videos as you explain them in a much better way than those in Udemy.

[@hyzer.flipr0]

This was an excellent video. Thank you.

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Loved the explanation! (And the Beatles) A channel worth subscribing.

Your channel is amazing!

[@RonanClancy]

Excellent! Great explanation! Thanks

[@Halilbayrak9191]

Thank you very much ,it is very clear !!

[@MrAikien]

Great video! 👌👍 Thanks! 🙏

[@DavidMerinos]

This is applyable to C/C++ too and is usually an interview questiton (differences between Array and Linked lists)

[@forbidden-cyrillic-handle]

Oh, wow. Here they usually go asking about very specific and obscure algorithm that you have only 0.001% chance to know. And if you happen to know the answer and get the job, you later realize that specific algorithm is never used in their projects.

[@wristdisabledwriter2893]

Perfect timing I meant to ask you for this

[@AbdullohHamidullayev-qm3ls]

thank you so much for your lessons

[@noteuser15]

Bro, you are helping me a lot! I am falling way behind in my Java class, and my teacher is not helping me. Your videos are a boon! thanks

[@fc6827]

Good video, never really thought about this, and have been doing this for 7 years now

[@LuisAguilar-hp3lq]

Loved your explanation

[@TheCanuckman75]

Wow this channel is amazing. Subscribed! I have an interview tomorrow, and will definitely be using your videos to learn Java if it doesn’t go well!

[@CodingWithJohn]

Hope it goes well! And also hope you come back to learn more even if it does go well 😀

[@TheCanuckman75]

@@CodingWithJohn will definitely use your channel to learn!

[@TheCanuckman75]

@@CodingWithJohn I think it went well!! Will probably hear back some time next week! Thank you again!

[@danielcisa107]

Really like your vids and the way you explain.. Gj

[@flytoinfinityvivi]

This is the most amazing course ever! Exactly what I want to know regarding of why use one from the other. Best examples and I got it rightaway. This guy is genius and should be a professor instead.

[@Sear-hh4gf]

You’re awesome John, thank you!

[@fcoGaz]

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[@sekharreddy3236]

You are awesome sir, appreciate your detailed explanation

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This is the guy that makes life easy when it comes to Java .....Beautiful explanation 😄

[@jordanmcguire2344]

Thank you so much. I am glad I watched this.

[@tian_wijaya]

great explanation, thank you

[@Zalaniar]

Great video! I've actually never used either of these collections, as my java teacher had a preference for Vector and it stuck with me. So that leads me to a question: how do Vector and other collection classes play into the discussion and when would you use them over ArrayList?

[@DavisTibbz]

Vectors are no longer recomnended in Java, old, and poor performance. According to java official documentation, avoid it

[@bambangariyanto2306]

i love Java, so sad some programmers are leaving it.. but i am glad, someone like you learn a java.

[@Anonymous-ot2kk]

Thanks for this video 🙏

[@atulaggarwal2897]

Please provide more information on time complexity of operations in case of ArrayList and LinkedList

[@bradcabbage5132]

i love you john ur keeping me hungry for more knowledge

[@badwrong]

The traversal of a linked-list is slower than shifting all the elements of an array list by one. So, with larger amounts of data modifying a linked-list becomes exponentially slower and produces many cache misses.

[@jvsnyc]

ArrayList is still great if you are adding tons of stuff only to the end. It only needs to move stuff over when adding *not* at the end, otherwise it just places the element at the end and updates the current size. Additionally, it only needs to create a new array and copy everything over when the reserved capacity is exhausted. If you are keeping a reference to some node deep in the midst of the LinkedList, and adding or removing around *that*, then the LinkedList is faster. Also, if for some reason you are often adding and removing right at the beginning, a LinkedList comes into its own. Lastly, there is more memory overhead and less cache coherence with LinkedList. A funny quote I remember: “Does anyone actually use LinkedList? I wrote it, and I never use it.” Joshua Bloch Searching that gives some interesting information on it. As you said tho, for small data sizes, either of them would work great, you will likely never notice a difference unless your data gets larger.

[@DanielNit]

I use LinkedLists a lot for exactly the memory reason. Namely no memory fragmentation. Where an ArrayList occupies new bigger and bigger chunks as it grows, it leaves the old memory segments behind that are too small for the new List to fit into. Thus memory will easily look like swiss cheese with lots of unuseable free memory inbetween. The LinkedLust however can place its nodes into "any tiny spot" and thus saturate memory more dynamically. So while a LL sure performs worse as a main read-object, the write-benefits outweigh for temporary and dynamic data in my opinion.

[@jvsnyc]

@@DanielNit what you describe can be true in some circumstances, I believe it is less relevant in garbage collected systems with a mature and evolved collector. That is, the jvm has freedom to do a lot of heap cleanup behind the scenes. It was relevant in c and c++ for me however. If you are often adding or removing far from the ends the linked list is great. Arraydeque comes into its own when all or most of the adds and removes are at or near either or both ends. For small data, none of this makes much difference. For larger data profiling one's heap interactions can answer the question for the actual combination of data, code and jvm/gc implementation.

[@DanielNit]

Sure in managed languages like Java, it likely wont have that much of an impact, but as most things, it is situational. Henve why I specifically refered to dynamic and temporary use cases and it all surely only matters at bigger sizes. So tens of thousands, millions and more, as well as services/servers that continously run for a long time. That said, I didnt doubt your expertise or anything but it is merely my quirk with fragmentations from many languages with absolutely no solutions against these issues but similar data structures as described in this video. Also happy new yeah ^_^

[@jvsnyc]

@@DanielNit you too. Fragmentation is a huge issue in non-managed systems if ignored. Large commercial systems I worked on addressed it on at least two levels and it was still something to consider even then. I have spent less time so far monitoring pure Java systems, and gc is one area that may change and evolve more as it doesn't affect the api's. Happy new year!

[@schwingedeshaehers]

@@DanielNit if there is place behind the current array, it should expend in that, and don't take a new place. Else the question is, if the overhead of the linked list is worth it, to not take a chunk of memory. (Together with the get time complexity)

[@nicholaswhite7351]

Thank you for you work.

[@JonasKeil]

This video is great!! 🎉

[@elixerprince_art]

You my good sir are a great Java teacher!