Install Sun JRE in Mint

Download JRE from www.java.com: jre-7u9-linux-x64.tar.gz (as of 201212)
to ~/Downloads

$ sudo mkdir -p -v /opt/java/64
$ cd Downloads && tar xvzf ~/Downloads/jre-7u9-linux-x64.tar.gz
$ sudo mv -v ~/Downloads/jre1.7.0_09 /opt/java/64
$ sudo update-alternatives --install "/usr/bin/java" "java" "/opt/java/64/jre1.7.0_09/bin/java" 1
$ sudo update-alternatives --set java /opt/java/64/jre1.7.0_09/bin/java

note:
run sudo update-alternatives –auto java to let system decide which java version to use

$ sudo update-alternatives --auto java
update-alternatives: using /usr/lib/jvm/java-6-openjdk-amd64/jre/bin/java to provide /usr/bin/java (java) in auto mode.

source:
https://sites.google.com/site/easylinuxtipsproject/java