Java Performance - ArrayLists versus Arrays for lots of fast reads -

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I have a program where I need to make random access to 100,000 to 1,000,000 such as the inventory object less time Is read in a cellular automata-such as possible for a program (as in milliseconds) I think the update algorithm I am using is already optimized (keeps track of active cells efficiently, etc.). The list needs to be changed, but this performance is not as important as it is, I am thinking that the difference in the timeline is read in such a short time, if there is a difference in the use of the array instead of the Ariel, Does not fall. Currently, I am using array list.

EDIT: I forgot to say: I am just storing the integer, so another aspect is using the integer cover class (in the case of Arrestist) vs INS (in case of Arrays ) Does anyone know that to use ArrayList will actually need 3 indicator lookup (for an ArrayList, for an underlying array, and for an integer-> int) where the array is only 1 (array Need address + offset Fraction)? Will hotspot optimize additional look ups? Edit 2: Besides, I also forgot that I need to write random access (write, not entry). Now you have mentioned that your arrays are actually of antiquity, collection-in-the-file in the library, Consider using primitive-type classes. / P>

@Witching Important (tenfold!) Speed ​​up report using comments in your application - see comments. Flip-side is that the Trove archive types are not compatible with Java's standard archive API. So the traction (or similar library) will not answer in all the cases.


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