kindly follow these links
Java in Ubuntu
#Ubuntu Team java documentation page
Ubuntu help Java page
LUcid release Ntes # always a good idea to read through theese
Ubuntu lucid release notes
These links should help you answer you questions n this topic. If you encounter any errors while on this endeavor please post them to this thread so either my self or other more knowledgeable LQ members can help you trouble shoot you issues. I would also recommend that you bookmark the ubuntu team documentation
Don't forget Google is your Friend!