ArrayList vs LinkedList in Java

ArrayList vs LinkedList in Java

I used to think ArrayList and LinkedList are basically the same thing.
Because when you’re coding, both feel similar — you just call add(), get(), and move on.

But after using them a bit more, the difference starts to show. Not immediately, but when the list gets bigger or when you keep modifying it.

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ArrayList

ArrayList is kind of like a normal array, but it grows automatically.

So everything is stored in order, one next to another. Because of that, accessing elements is quick.
If you know the index, you’ll get the value instantly.

The only thing is, inserting or deleting in between isn’t that smooth.
Other elements need to shift, so it takes some extra work internally.

ArrayList<Integer> list = new ArrayList<>();
list.add(10);
list.add(20);
System.out.println(list.get(1));

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LinkedList

LinkedList works differently. It doesn’t store elements in a continuous way.

Each element is connected to the next one (and previous too). So it’s more like a chain.

Because of this, inserting or removing elements is easier — it just updates the links.
But accessing is slower, since it has to go step by step.

LinkedList<Integer> list = new LinkedList<>();
list.add(10);
list.add(20);
System.out.println(list.get(1));

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What I understood

Instead of remembering all details, I just think like this:

If I need fast access → I use ArrayList
If I keep adding/removing → LinkedList makes more sense

That’s how I usually decide.

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In practice

Most of the time, I end up using ArrayList. It’s simple and works fine for general cases.

LinkedList is useful, but I don’t reach for it unless there’s a clear reason.

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Final note
Both are part of the same interface, but they behave differently inside.

So choosing one depends on what your program is doing more — reading or modifying.

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