ArrayList Tip - Printable Version

ArrayList Tip - Printable Version

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ArrayList Tip - Project Evolution - 01-01-2010

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.

RE: ArrayList Tip - Qkyrie - 01-09-2010

ahh, nice one, never thought of that. That's something to remember, weird that I haven't stumbled upon this before..

thanks
Q

RE: ArrayList Tip - Ⱳąŗɗ - 03-13-2010

I see Big Grin

tyvm, I'll keep this in mind when using integer Arrays.