How to find free space in an ArrayList...

Question

Hi,
I have an ArrayList with data randomly assigned to different indexs of the ArrayList.
I want to find out where the "gaps" are within the ArrayList... For Example There would be data in index 0,1,2,3,5 but not in index 4 . How would I go about finding this information.
Thanks
Chris

Answer 1

jwenting wrote:
kajbj wrote:
Praveen_Forum wrote:
I don't think we have to look into the free space's for ArrayList, as it is a dynamic growing arraylist you can just keep on adding the stuff in it takes care of filling all the empty spaces
I am i right?No, it will not fill a gap.in fact it will, after a fashion.
When you remove an item the remaining items are reshuffled to close the gaps.
When you try to insert an item beyond the last position (so at list.size()+2 or greater) you will get an error, and the insert will fail.I was more thinking of a situation like this:
        strings.add("One");
        strings.add("Two");
        strings.add("Three");
        strings.set(1, null);
        System.out.println(strings);The element at index 1 will be null (a gap in my view), since remove won't cause a gap.
Kaj