# Root
user@host:~$ sudo su

# Change according to your wish, for example this is installation directory
root@host:~# mkdir -p /usr/lib/jvm

# Optional you can copy or directly extract., this is old version change according to your need
root@host:~# cp -i jdk-7u11-linux-i586.tar.gz /usr/lib/jvm/
root@host:~# cp -i jre-7u11-linux-i586.tar.gz /usr/lib/jvm/

# change directory
root@host:~# cd /usr/lib/jvm/

# Extract jdk and Jre
root@host:/usr/lib/jvm# tar -xvf jdk-7u11-linux-i586.tar.gz
root@host:/usr/lib/jvm# tar -xvf jre-7u11-linux-i586.tar.gz

# If not needed delete
root@host:/usr/lib/jvm$ rm -rf *.gz

# confirm that these two are extracted
root@host:/usr/lib/jvm# ls -1
jdk1.7.0_11
jre1.7.0_11

# Configure according to foldername highlighted in blue color
root@host:/usr/lib/jvm# sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/lib/jvm/jdk1.7.0_11/bin/javac" 1

root@host:/usr/lib/jvm# sudo update-alternatives --install "/usr/bin/java" "java" "/usr/lib/jvm/jre1.7.0_11/bin/java" 1

root@host:/usr/lib/jvm# sudo update-alternatives --set "javac" "/usr/lib/jvm/jdk1.7.0_11/bin/javac"

root@host:/usr/lib/jvm# sudo update-alternatives --set "java" "/usr/lib/jvm/jre1.7.0_11/bin/java"

# On successful installation you should be able to see following
root@host:/usr/lib/jvm# java -version
java version "1.7.0_11"
Java(TM) SE Runtime Environment (build 1.7.0_11-b21)
Java HotSpot(TM) Server VM (build 23.6-b04, mixed mode)

root@host:/usr/lib/jvm# javac -version
javac 1.7.0_11