I think your implementation is overall very good, two small comments:


Improving readability for return statement in hasNext to return examples.size() != index;
Making the examples field final: private final List&lt;Vector&gt; examples;


However, if the Vector class here is java.util.Vector you should know that it is considered deprecated in favor of the ArrayList class.

Also, since you create your iterator from a List&lt;Vector&gt; you could get an Iterator&lt;Vector&gt; by calling list.iterator();

Iterator Implementation
When the anime starts and until episode 8, they attached a cell-phone to the phone-microwave and sent a message to that specific phone to trigger sending D-Mails. But in episode 8 


   Ruka sent a D-Mail to her mother pager


and then in episode 9


   Faris sent a D-Mail to (probably) herself


So I'm wondering if there is a plot whole somewhere in the story, or did they figure out a way to send D-Mails from any phone to any phone? 

As a side question previously it was mentioned that how they can set D-Mail's time of Arrival:


   each second on Phone-Microwave meant an hour going back, so I'm wondering how did they manage to set microwave time to 87600 (10 years)?

