help: composition & object references critique pls

From: javac (javac_at_mail.com)
Date: 04/26/04 

Date: 26 Apr 2004 11:58:44 -0700

object "LifeForm" has an immutable object "Location"

I want "change" the immutable Location object by generating a new
Location, but it ain't working the way i wants it to. how do i get
this to work, pls?

also, what's the best forum for a question such as this?

i've adapted examples from:
http://java.sun.com/docs/books/performance/
http://java.sun.com/docs/books/effective/

my code:
http://www.geocities.com/cjavacjava/src/

javac@mail.com