Debian下install JDK

vim .bashrc
export JAVA_HOME=/var/lib/jdk1.6
export PATH=$PATH:$JAVA_HOME/bin
export CLASSPATH=$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
source .bashrc

update-alternatives --install /var/lib/jdk1.6/bin/java java /var/lib/jdk1.6/bin/ 300

java -version
#success done!!!