More specifically, we're always happy to help, but we WON'T do your homework for you from the ground up.
Let's take number 1. Do you know what polymorphism is, even if it's a verbatim reiteration of a definition from the glossary in some text book? Do you know what encapsulation is? Do they work together or are they diametrically opposed (or something inbetween)?
Actually that code is not entirely correct. It would be:
JF: ...does Iterator only modify vectors?
All implementations of the java.util.Collection interface have an iterator() method which returns an Iterator which can iterate over the elements of that Collection [ August 31, 2006: Message edited by: Garrett Rowe ]
Some problems are so complex that you have to be highly intelligent and well informed just to be undecided about them. - Laurence J. Peter