public int getLastElement2(int[] nums)

All arrays will have 4 elements.

If the arrays you're testing all have the same length,
you don't have to use the expression [len-1].
You can just use the position number itself.

For example:
If the list has 4 elements, use nums[3] for int[] nums.
If the list has 10 elements, use words[9] for String[] words.
If the list has 3 elements, use list[2] for int[] list.

So if the list has 4 elements, 3 is the position of the last element.

public String getLastElement2(String[] words) {
  String last = words[3];
  return last;
}

If, however, the list can be ANY size, use an expression.

public String getLastElement2(String[] words) {
  int len = words.length;
  String last = words[len-1];
  return last;
}