How can we get the last added element in ArrayList. I find this that explain how to get the last element, but is the last added element always the last element ?
Yes for ArrayList, It preserves the order of insertion
If you explicitly add the element at particular position by specifying index add(), in this case you need to set insertion time by customizing ArrayList implementation and while retrieving the latest inserted element consider that time in calculation
or better have a reference pointing to last inserted item as Marko Topolnik suggested, also maintain it on removal
Better thing would be use LinkedHashSet, if you are not concerned about uniqueness property of set