What you want is a very expensive operation in an ArrayList
. It requires shifting every element between the beginning of the list and the location of C
down by one.
However, if you really want to do it:
int index = url.indexOf(itemToMove);
url.remove(index);
url.add(0, itemToMove);
If this is a frequent operation for you, and random access is rather less frequent, you might consider switching to another List
implementation such as LinkedList
. You should also consider whether a list is the right data structure at all if you're so concerned about the order of elements.
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