Sun Java

On Ubuntu

$ sudo apt-get install sun-java6-bin sun-java6-jre sun-java6-jdk
$ sudo update-java-alternatives -s java-6-sun
$ sudo vi /etc/jvm

add /usr/lib/jvm/java-6-sun

    /usr/lib/jvm/java-gcj
    /usr/lib/jvm/ia32-java-1.5.0-sun
    /usr/lib/jvm/java-1.5.0-sun
    /usr
set environment variable
$ vi $HOME/.bashrc

add following

export JAVA_HOME=/usr/lib/jvm/java-6-sun-1.6.0.XX

export PATH=$PATH:$JAVA_HOME/bin:$PATH:$HOME/bin

check:

$ java -version

$ JAVA_HOME

On Fedora

# yum install sun-java6-bin sun-java6-jre sun-java6-jdk
# yum update-java-alternatives -s java-6-sun
# vi /etc/jvm

add /usr/lib/jvm/java-6-sun

    /usr/lib/jvm/java-gcj
    /usr/lib/jvm/ia32-java-1.5.0-sun
    /usr/lib/jvm/java-1.5.0-sun
    /usr
set environment variable
$ vi $HOME/.bashrc

add following

export JAVA_HOME=/usr/lib/jvm/java-6-sun-1.6.0.XX

export PATH=$PATH:$JAVA_HOME/bin:$PATH:$HOME/bin

check:

$ java -version

$ JAVA_HOME