How to install Java on ubuntu

Download J2SDK package from java.sun.com or find the mirror on Google. download j2sdk-1.4-2_05.bin. remember download the *.bin ,don't rpm.
run the file ./j2sdk-1.4.2_05.bin
and j2sdk1.4.2_05 folder will be created, with root, move this folder to /usr/share, with
heri@neutrino~]$ sudo mv j2sdk1.4.2_05 /usr/share
make symbolic link, with
heri@neutrino~]$sudo ln -s /usr/share/j2sdk1.4.2_05 /usr/share/java
Open and edit /etc/bash.bashrc. fill this in the last row :
JAVA_HOME=/usr/share/java export JAVA_HOME PATH=$JAVA_HOME/bin:$PATH export PATH
then in terminal type this
heri@neutrino~]$java --version
if you can see the java version. it means that the configuration is right

thank's to my friend for this information
sorry for my bad english

Neutrino