tar -xzvf jdk-8u151-linux-x64.tar.gz -C /usr/local/src
sudo vim /etc/profile
1.编辑/etc/profile # JAVA export JAVA_HOME=/usr/local/src/jdk1.8.0_151 export JRE_HOME=$JAVA_HOME/jre export CLASS_PATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar:$JRE_HOME/lib export PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin 2.使环境变量即刻生效 $>source /etc/profile 3. 替换默认的java $> rm -rf /etc/alternatives/java $> ln -s /usr/local/src/jdk1.8.0_151/bin/java /etc/alternatives/java 4.进入任意目录下,测试是否ok $>cd ~ $>java -version