Properly removing an Integer from a List

Question

Here\'s a nice pitfall I just encountered. Consider a list of integers:

List list = new ArrayList();
list.add(5);
list.add(6);         


        

Answer 1

You can use casting

list.remove((int) n);

and

list.remove((Integer) n);

It doesn't matter if n is an int or Integer, the method will always call the one you expect.

Using (Integer) n or Integer.valueOf(n) is more efficient than new Integer(n) as the first two can use the Integer cache, whereas the later will always create an object.