ArrayList Tip

[Project Evolution]

When using an ArrayList that accepts integer objects like so,

Code:

ArrayList<Integer> list = new ArrayList<Integer>();

Be sure to call the remove method and cast it with an integral value in the list becasue the ArrayList class has both the remove(integer) and remove(Object).

Basically we have,

Code:

ArrayList<Integer> list = new ArrayList<Integer>();
list.add(1);
list.add(2);
list.add(3);

If you wanted to remove the number 2 in the list you would invoke,

Code:

list.remove((Integer) 2);

because if you call the remove method without casting, it will remove the object at index 2. Heres how this happens,

Code:

list.remove(2);

If it removes what is at index 2, it will remove the number 3 because always remember, Arrays start at 0 not 1!

Thanks.