Basically, the package manager is your best friend when you are connected to the internet. If you are not, you are going to have to deal with the dependancy hell yourself. That's not good! I advise you don't use the package manager at all for installing java if you are not connected to the internet.
Sun provides java installation files for linux (they have the '.bin' extension). Install those instead of the deb file, for they should have most dependancies included. Check Sun's website. If your ISP is banned from SUN, you can always use some anonymizer, they are easy to find on google.
Of course, if you are connected to the internet, then USE the package manager, it makes your life a lot easier. In this case, you have to enable the 'multiverse' repository in order to install Sun's java, because this software is plagged with license problems. It is still a lot easier this way if you can.
Check your /etc/apt/sources.list file for those lines (add multiverse if necessary):
hardy universe multiverse
hardy-security universe multiverse
hardy-updates universe multiverse
Hope this helps...