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POArray vs. ArrayList when position is important
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copied!<p>I'm a Java newbie with a quick Array vs. ArrayList question. I have an array of objects that can grow or reduce in size, but it's very important for me to maintain the position they were in relative to each other in the array. I'm thinking because of this I need to use Array instead of an ArrayList which can condense/shift elements around if they are removed/added.</p> <p>The practical example: In my first Java application that I'm slugging through to learn the nuances of this language I'm making a basic poker game simulator. I have Player objects in an array representing the seats they are sitting at, and it's important to know where the dealer button (index) was placed before rotating it. Players being removed or added from an ArrayList will change the indices of the players, and that can throw off the next Player to get it. Dealer button movement is very player-placement specific.</p> <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> <p>EDIT:</p> <p>To further clarify, let me give an example of why ArrayList's element movement won't work: Take three players and their indices in the array:</p> <p>0 : Player One (Dealer button) 1: Player Two 2: Player Three</p> <p>If player two (index one) gets up from the table before the dealer button is rotated, depending on the rules player one will <em>keep</em> the button and the blinds will be adjusted accordingly (there's other variants of this rule, but the one I like to use). In an ArrayList, the internal array will be condensed and player three will end up getting the button an extra round before he should. I need to track the empty seat that was active during the hand but was emptied before the round was over and the button moved.</p> <p>I'm starting to realize that the concept of a "seat" is going to be more complicated, I need to track state on it, including "player just sat down while hand in progress," "player got up while hand in progress," etc. @Stephen P - I think you're right about this, I'm going to need to track them separately and cannot use a simple array structure to determine the logic. Timing of when the elements are added and/or removed is paramount to the application logic, and simply examining if an element is there or not won't cut it.</p> <p>For the Seats themselves, I'm learning towards ArrayList since the Seats will now <em>always</em> be there, no empties. The Seat will just have a reference to the Player object if one is sitting there as well as WHEN that player arrived. Thanks everyone!</p>

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