Question

ATTENTION: I CANNOT know if doSomething will remove the element or not. This is an exceptional case that my data structure needs to handle.

My problem is simples:

int size = list.size();
for(int i = 0; i < size; i++) {
   MyObj mo = list.get(i);
   mo.doSomething();
}

Now if doSomething() remove mo from the list, I eventually get an ArrayIndexOutOfBounds because the list has now shrunk.

What data structure should I use to allow iteration with the possibility of removing? I can NOT use an iterator here, in other words, I can NOT make doSomething return a boolean and call iterator.remove(). The data structure has to somehow handle the situation and continue to iterator through the rest of the elements still there.

EDIT: I CANNOT know if doSomething will remove the element or not. This is an exceptional case that my data structure needs to handle.

Part II => Making a smart listeners notifier to avoid code duplication everywhere

Answer 1

You can use an ArrayList, for example, as long as you update the index and size when something is removed.

List<MyObj> list = new ArrayList<MyObj>();
int size = list.size();
for(int i = 0; i < size; i++) {
    MyObj mo = list.get(i);
    mo.doSomething();
    if (size > list.size()) {
        size = list.size();
        i--;
    }
}

This only works if the item removed is the last one examined. For other changes to the list you will have to have more complicated logic.