下載jdk-7u67-linux-x64.tar.gz
sudo tar zxvf jdk-7u67-linux-x64.tar.gz -C /usr/lib/jvm
export JAVA_HOME=/usr/lib/jvm/jdk1.7.0_67
export JRE_HOME=${JAVA_HOME}/jre
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib
export PATH=${JAVA_HOME}/bin:$PATH
sudo update-alternatives --install /usr/bin/javac javac /usr/lib/jvm/jdk1.7.0_67/bin/javac 300
java version "1.7.0_67"
Java(TM) SE Runtime Environment (build 1.7.0_67-b01)
Java HotSpot(TM) 64-Bit Server VM (build 24.65-b04, mixed mode)