Most memory efficient way to grow an array in Java?

Question

I\'m not too concerned about time efficiency (the operation will be rare), but rather about memory efficiency: Can I grow the array without temporarily having all th

Answer 1

Obviously, the important bit here is not if you concatenate the arrays or copy them over; what's more important is your array growing strategy. It's not hard to see that a very good way to grow an array is always doubling its size when it becomes full. This way, you will turn the cost of adding an element to O(1) as the actual growing stage will happen only relatively rarely.