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POJava - Most efficient way to store a bunch of objects and later iterate through them, where the amount is unknown and order doesn't matter?
 

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  1. POJava - Most efficient way to store a bunch of objects and later iterate through them, where the amount is unknown and order doesn't matter?
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    <p>By "the amount is unknown" I mean that at the time of creation of whatever data structure I use to store them in, I don't know how many objects there will end up being to store. Once I have all these objects, I want to be able to iterate through all of them, and it doesn't matter what order I visit them in. I'm wondering what would be the most efficient (in time and space, but mostly time) way to go about doing this in java. </p> <p>I <em>do</em> have a cap on the max number of objects that there will be in the thing, so I was considering just making an array of this size. But I didn't want to waste space, and the array could end up being more than twice as big as the number of elements that actually get stored in it. </p> <p>I was also considering a LinkedList, because I thought maybe it would be more efficient to iterate through it than having to create an iterator from something else like a hashmap and iterate through that. But I don't know how expensive it is to create an iterator from various java data structures. </p> <p>So, any ideas?</p>
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    1. COAre we talking 10? 10000? 10G? Size does matter.
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    2. COThe various data structure iterators are all tiny objects with similar creation costs.
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    3. CO@ptyx: well, we're talking decently small (like maybe 50 objects at most per data structure), but it's going to be something that's done (storing new objects and iterating through them) millions of times if not more.
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