安装JDK

下载并解压jdk-8u91-linux-x64.tar.gz到/opt

执行：

alternatives --install /usr/bin/java java /opt/jdk1.8.0_91/bin/java 2

alternatives --config java

alternatives --install /usr/bin/jar jar /opt/jdk1.8.0_91/bin/jar 2

alternatives --install /usr/bin/javac javac /opt/jdk1.8.0_91/bin/javac 2

alternatives --set jar /opt/jdk1.8.0_91/bin/jar

alternatives --set javac /opt/jdk1.8.0_91/bin/javac

~/.bashrc 中增加：

export JAVA_HOME=/opt/jdk1.8.0_91

export JRE_HOME=/opt/jdk1.8.0_91/jre

export PATH=$PATH:/opt/jdk1.8.0_91/bin:/opt/jdk1.8.0_91/jre/bi