Re: Container reqs

[paul.duquennoy@wanadoo.fr (Paul Duquennoy)]

Simon Wright <simon@pushface.org> wrote:

> lutz@iks-jena.de (Lutz Donnerhacke) writes:
> 
> > * Jeffrey Carter wrote:
> > >Lutz Donnerhacke wrote:
> > >> >By "ordered" I mean a structure where the position of an Element within
> > >> >the structure is determined by the value of the Element. What is
> > >> >the next Element in the structure if the current Element has moved?
> 
> What would the Java collections classes do under such circumstances?

Assume that you have (in Java) : 

   Collection c = new ArrayList (10);
   Iterator   i = c.iterator();

If you do c.remove (...); and try i.next(), you get an exception. But
the iterator has a remove() method that removes the last element fetched
object from the collection while keeping the integrity of the iterator.

If you add a new element to the collection, you will get an exception at
the next call of an iterator method.

So do not use any updating method of the collection itself while you are
iterating over it. Use only the "remove" method of the iterator.