After I upgraded my Ubuntu to 10.04, I found that the sun-java6 package was removed from repository which means you can't get it by running "sudo apt-get install sun-java6". I did the Google search, and found following statement from 10.04 LTS release notes:
Sun Java moved to the Partner repository
Now, if you want to install sun-java6, you have to do the following steps:
- add-apt-repository "deb http://archive.canonical.com/ lucid partner"
- sudo apt-get update
- sudo apt-get install sun-java6 sun-java6-plugin
- sudo update-java-alternatives -s java-6-sun