# java -version

# rpm -qa | grep jdk

# yum remove -y java-1.7.0-openjdk-1.7.0.99-2.6.5.0.el6_7.x86_64

# yum remove -y java-1.6.0-openjdk-1.6.0.0-11.1.13.4.el6.x86_64

2.删除原jdk1.8

# cd /usr/local/

# rm -rf jdk

# rm -rf jdk1.8.0_73

3.进入到目录下并上传

# cd /server/tools/

# rz -y 

jdk-7u79-linux-x64.gz

4.安装jdk1.7

# tar xf jdk-7u79-linux-x64.gz -C /usr/local/

# ln -s /usr/local/jdk1.7.0_79/ /usr/local/jdk

# chown -R root.root /usr/local/jdk

5.配置java的环境变量

# vim /etc/profile

末尾添加

export JAVA_HOME=/usr/local/jdk

export PATH=$JAVA_HOME/bin:$JAVA_HOME/jre/bin:$PATH

export CLASSPATH=.$CLASSPATH:$JAVA_HOME/lib:$JAVA_HOME/jre/lib:$JAVA_HOME/lib/tools.jar

配置生效

# source /etc/profile

6.查看jdk版本信息

# java -version

java version "1.7.0_79"

Java(TM) SE Runtime Environment (build 1.7.0_79-b15)

Java HotSpot(TM) 64-Bit Server VM (build 24.79-b02, mixed mode)