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collection.size() vs. array.length

paul wheaton
Trailboss

Joined: Dec 14, 1998
Posts: 20729
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In the article at http://java.oreilly.com/news/javaperf_0900.html the advantages of not having collection.size() used in the for loop are pointed out. Would this apply equally to array.length?


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Jack Shirazi
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Joined: Oct 26, 2000
Posts: 96
No. Java arrays (e.g. char[], Object[], not collection objects) cannot change size. So the value is a constant for any one array, and the loop has a constant value to compare against. The problem with collection.size() is that it makes a method call for every iteration of the loop.
 
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