How to Upgrade Jdk After install in linux

hii...

i want to upgrade my java version 1.4.2 to 1.6 in linux plateform after installing JDK. so what are the steps & commands in linux to upgrade it . Please Help me ...

I would leave the older version of JDK in place for the moment just in case. You can delete it later onece you are satified that you no longer need it.

Download the new JDK version from Sun/Java and install it wherever you like. All you need to do then is set JAVA_HOME to point to the new JDK instead of the old JDK.