The libraries have changed quite a bit, but the language is pretty much the same. The only thing I'd call a major difference is generics. Aside from that, it's mostly just bells and whistles (like enums, varargs, for-each loops).
I would buy a new book, as a couple newer classes came out since, but you should see them as depreciated, or suggestions in the javadoc to use the newer classes. I think Vector was one, and StringBuilder vs whatever the older one was, lots of other ones too.
I'd get a book they're cheap, just skim it over and look at the structure and classes and how generics work.