Is it considered a best pratice to initialize Collections ( eg: Arraylist ) with initial capacity ?
From my observation through docjar, it looked like initialization reduced need for 'expansion' of initial array and also reduce the size, of internal datastructure due to resizing.
As the comment mentions, if you know the number of elements that will be eventually needed, then it will gain you some performance since you do not have to re-allocate the backing array when the number of elements increases to exceed the current capacity.
However, there is a tradeoff because if you can't estimate it well (within an order of magnitude), then you may waste memory by allocating too much at the beginning.
