We all know you can't do this:
for (Object i : l) { if (condition(i)) { l.remove(i); } }
ConcurrentModificationException etc... this apparently works sometimes, but not always. Here's some specific code:
public static void
main(String[] args)
{ Collection<Integer> l = new ArrayList<>();
for (int i = 0; i < 10; ++i)
{ l.add(4); l.add(5); l.add(6); }
for (int i : l)
{ if (i == 5) { l.remove(i); }
}
System.out.println(l);
}
This, of course, results in:
Exception in thread "main" java.util.ConcurrentModificationException
... even though multiple threads aren't doing it... Anyway.
What's the best solution to this problem? How can I remove an item from the collection in a loop without throwing this exception?
I'm also using an arbitrary Collection here, not necessarily an ArrayList, so you can't rely on get.