Can you reset the counter of a for-each Loop?

Question

since there's no accessible counter or i in there to reset to zero.

is there any way to play around with continue or break to achieve that?

class CommandLine {
  public int[] sort(int array[]) {
     int temp;
     for (int i=0; i<array.length-1; i++) {//must have used for-each
            if (array[i] > array[i+1]){

                temp = array[i];
                array[i] = array[i+1];
                array[i+1] = temp;
                i=-1;

            }//if end
    }//for end

    return array;

  }//main end
}//class end

I've been asked to write a sorting algorithm with a for-each loop — James, Mar 23 '15 at 21:01
Perfect case of forcing you to implement insertion-sort :) bu making it look like you have choice. — zubergu, Mar 23 '15 at 21:07
yes I'm free to do anything I want with my current knowledge (which is not much) but use for-each at all costs — James, Mar 23 '15 at 21:10
suggested read: https://meta.stackexchange.com/questions/66377/what-is-the-xy-problem — zubergu, Mar 23 '15 at 21:14

score 3 · Accepted Answer · answered Mar 23 '15 at 21:02

Generally, there is no way of doing this: the iterator that is used to "drive" the for-each loop is hidden, so your code has no access to it.

Of course you could create a collection-like class that keeps references to all iterators that it creates, and lets you do a reset "on the side". However, this qualifies as a hack, and should be avoided.

If you need a way to reset the position of your iteration back to a specific location, use a regular for loop.

score 1 · Answer 2 · edited May 23 '17 at 12:18

1

No, the for each loop internally does not use any counter. Therefore, just use an usual loop like:

for (int i = 0; i < myCollection.size(); i ++) {
    // do something
}

More information: Is there a way to access an iteration-counter in Java's for-each loop?

edited May 23 '17 at 12:18

Community

1
1

answered Mar 23 '15 at 21:02

flogy

906
4
16

Please, don't call it `myArray` when It in fact is a `Collection`. That's somewhat confusing. – dhke Mar 23 '15 at 21:03
1

Thanks for the hint, fixed it. – flogy Mar 23 '15 at 21:04

Can you reset the counter of a for-each Loop?

2 Answers2