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copied!<blockquote> <p>Long story short - is using an Array the best way of handling elements in an array-type structure that need to maintain their position in the array? Is there a better method or logic to accomplish this? I apologize for the simple question but I couldn't find any other alternatives and wanted to confirm that this is the best route to take.</p> </blockquote> <p>Position shouldn't be your most important criterion for choosing array vs. ArrayList, at least I don't believe it should be.</p> <p>Arrays are covariant, and more performant most of the time. They mix poorly (if at all) with Java generics which is really kind of a big deal a lot of the time. You cannot create a reference to a new instance of an array of a non-reifiable type (though you can receive one, but buyer beware).</p> <p>ArrayLists, as a part of the Java Collections API, are invariant. For this reason they work much better with Java generics and, according to Joshua Bloch (Essential Java, 2nd Ed), should be favored much of the time. ArrayLists should often be less performant (and less concise) than arrays. Moreover, as part of the Java Collections API, ArrayLists are more flexible because they extend the List interface which enables you to change implementations from ArrayList to any other List provided that your own class that implements the List is well encapsulated (i.e. the ArrayList is not part of your class's exported API).</p> <p>There are other differences, of course, but these are the ones that really stand out. If you were really concerned about performance, you could create your own List implementation that was backed by arrays (like ArrayList is) in order to get a feature or the API contract you really wanted. Otherwise, to me, it sounds like you should be using ArrayList (or even other Collection type such as Map (suggested)).</p>

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