install-jdk-on-ubuntu.sh

# before run this script, run sudo ls, type your password

sudo mkdir -p /usr/lib/jvm
sudo tar xvzf ./jdk-7u21-linux-x64.tar.gz -C /usr/lib/jvm

cd /usr/lib/jvm
sudo mv jdk1.7.0_21 java-7-sun

sudo update-alternatives --install /usr/bin/java java /usr/lib/jvm/java-7-sun/bin/java 300
sudo update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/java-7-sun/bin/javac 300
sudo update-alternatives --install /usr/bin/jar jar /usr/lib/jvm/java-7-sun/bin/jar 300
sudo update-alternatives --install /usr/bin/javah javah /usr/lib/jvm/java-7-sun/bin/javah 300
sudo update-alternatives --install /usr/bin/javap javap /usr/lib/jvm/java-7-sun/bin/javap 300


# if you have more than one jdk installed
#
# sudo update-alternatives --config java


# config paths
# 
echo "export JAVA_HOME=/usr/lib/jvm/java-7-sun">> ~/.bashrc
echo "export JRE_HOME=\${JAVA_HOME}/jre">> ~/.bashrc
echo "export CLASSPATH=.:\${JAVA_HOME}/lib:\${JRE_HOME}/lib">> ~/.bashrc
echo "export PATH=\${JAVA_HOME}/bin:\$PATH">> ~/.bashrc
source ~/.bashrc


# test
#
java -version