Exception in thread "main" java.lang.IndexOutOfBoundsException: Index: 6, Size: 6

Question

I have a problem with this code

    List<String> listaTags = new ArrayList<String>();





    int i = 0;
    String current = listaTags.get(i);

    while (listaTags.size() > 1 && listaTags.contains("/".concat(current)) != current.contains("/")) {

        if (current.equals(listaTags.get(i + 1))) {

            listaTags.remove(current);
            listaTags.remove(listaTags.get(i + 1));

            if (i < 0) {
                i++;
            }
        }

        i++;

    }

    System.out.println("errore nel codice");

}

listatags has six elements

the error is:

Exception in thread "main" java.lang.IndexOutOfBoundsException: Index: 6,Size: 6

Can somebody help me?

The `if (i < 0)` statement can be removed - there is no way i can be less than zero. Your IndexOutOfBoundsException probably happens after a few cycles in the loop - the value current never changes so the loop will go on forever (you probably want to have `String current =` inside the while loop. — Stefan, Oct 16 '17 at 09:40
Indices in a list are zero-based, so if the list has 6 items, then valid index values are 0 to 5 (inclusive); 6 is an invalid index. — Jesper, Oct 16 '17 at 09:41
if list has 6 elements, then indexes of those elements are from 0 to 5. Element 6 does not exist — mlecz, Oct 16 '17 at 09:41

score 0 · Answer 1 · edited Oct 16 '17 at 10:53

0

this line

if (current.equals(listaTags.get(i + 1)))

is throwing an exception because in 'while' every time list size is greater than 1 and your i value reaches the value which is greater than the size of the list.

edited Oct 16 '17 at 10:53

Stanislav

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answered Oct 16 '17 at 09:43

sai

75
4

score 0 · Answer 2 · answered Oct 16 '17 at 09:57

Since the Size of the list is 6, so indexes are 0,1,2,3,4,5 (which is value of i in this case)

You are always increasing the value of i by 1 and when it is i = 5, it is throwing IndexOutOfBoundsException.

As a fix you can do

if (i < 5 && current.equals(listaTags.get(i + 1))) {...}

Exception in thread "main" java.lang.IndexOutOfBoundsException: Index: 6, Size: 6

2 Answers2