Update Java Runtime Environment (JRE) en Ubuntu (13.04)

update_jre.txt

Descargamos el JRE:
http://java.com/en/download/linux_manual.jsp

Instalamos:
$ sudo tar xvzf jre-7u45-linux-i586.tar.gz -C /usr/lib/jvm/
$ sudo chown root: /usr/lib/jvm/jre1.7.0_45/ -R
$ sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/jre1.7.0_45/bin/java 0

$ sudo update-alternatives --config java
Existen 2 opcioens para la alternativa java (que provee /usr/bin/java).

  Selección   Ruta                                     Prioridad  Estado
------------------------------------------------------------
  0            /usr/lib/jvm/java-7-oracle/jre/bin/java   4         modo automático
  1            /usr/lib/jvm/java-7-oracle/jre/bin/java   4         modo manual
* 2            /usr/lib/jvm/jre1.7.0_45/bin/java         0         modo manual

$ java -version
java version "1.7.0_45"
Java(TM) SE Runtime Environment (build 1.7.0_45-b18)
Java HotSpot(TM) Server VM (build 24.45-b08, mixed mode)


Actualizamos el plugin de Firefox
==================================
ls ~/.mozilla/
mkdir ~/.mozilla/plugins
ln -s /usr/lib/jvm/jre1.7.0_45/lib/i386/libnpjp2.so ~/.mozilla/plugins/

Abrimos el browser y verificamos
about:plugins
http://www.java.com/es/download/installed.jsp

Info:
http://java.com/en/download/help/linux_install.xml
http://www.ubuntu-guia.com/2012/04/instalar-oracle-java-7-en-ubuntu-1204.html