ubuntu 配置jdk

1. download jdk-8u91-linux-x64.tar.gz
2. 解压到/opt/jdk/jdk1.8.0_91/
3. 配置环境变量

sudo gedit /etc/profile  
export JAVA_HOME=/opt/jdk/jdk1.8.0_91 
export JRE_HOME=/opt/jdk/jdk1.8.0_91/jre  
export PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin  
export CLASSPATH=.:$JAVA_HOME/lib:$JAVA_HOME/jre/lib:$CLASSPATH  

4. 让配置生效

source /etc/profile