In a recent attempt to reduce my "Unread" mailbox, I went back in it marking as "Read" everything that has been, well, read. So it happened that I stumbled across a bug report I filed with Sun around 7 months ago (yes, that mailbox was deep), and went to see what became of it. You can see it here.
The problem I reported is that various iterator objects shipped with Sun's JRE aren't serializable. Looking at the bug's page, I noticed that the "Evaluation" field has been filled out with:
Iterators are not intended to be serializable. Probably.... Not a Defect.Wow. Whoever evaluated this wasn't particularly, to put it mildly, in short supply of short-sightedness. In accordance to this, the bug was marked as "Request for Enhancement".
Now please tell me if I see it wrong, and if there never-ever can arise a valid class design where a stateful object maintains certain aspect of its state by keeping an iterator into a collection, and said object should be serializable. At least for lists, the concept can even be emulated by holding a reference to the list object and an index variable, so it definitely doesn't sound like a very unsane idea.
Now, this admittedly might sound as a more esoteric case of serializing state that contains an iterator, but really, were I to use a "for" loop with explicit indexing instead of an iterator, it wouldn't have been a problem. Therefore, I can't see serializing an iterator to be such an off-the-wall idea to justify the anonymous Sun mouthpiece saying "Iterators are not intended to be serializable"?