Question

I have a list of ListIterator<PointF> as a class field. I fill it in method grow(). When i try to use iterators from this list i get ConcurrentModificationException.

ListIterator<ListIterator<PointF>> i = mPoints.listIterator();
while (i.hasNext()) {
    ListIterator<PointF> j = i.next();
    if (j.hasNext())
        PointF tmp = j.next(); // Exception here
}

I have no idea why does this code causes exeption in any method besides grow()

Answer 1

If the underlying list changes, the iterator that was obtained before that throws ConcurrentModificationException. So don’t store iterators in instance fields.