(1) Java JDK5 Install:
Append the following two lines into app source list: nano /etc/apt/sources.list
deb http://cn.archive.ubuntu.com/ubuntu/ jaunty multiverse
deb http://cn.archive.ubuntu.com/ubuntu/ jaunty-updates multiverse
sudo apt-get update
sudo apt-get install sun-java5-jdk
(2) Java JDK6 Install:
Append the following line into app source list: sudo nano /etc/apt/sources.list
deb http://archive.canonical.com/ubuntu maverick partner
sudo apt-get update
sudo apt-get install sun-java6-jdk
(3) Check the current java version
java -version
(4) Select Java version
sudo update-java-alternatives -l
sudo update-java-alternatives -s java-6-sun