jk安装

[root@localhost ~]# java -version
openjdk version "1.8.0_161"

[root@localhost ~]# rpm -qa | grep java
tzdata-java-2018c-1.el7.noarch
python-javapackages-3.4.1-11.el7.noarch
java-1.7.0-openjdk-1.7.0.171-2.6.13.2.el7.x86_64
java-1.8.0-openjdk-1.8.0.161-2.b14.el7.x86_64
java-1.7.0-openjdk-headless-1.7.0.171-2.6.13.2.el7.x86_64
javapackages-tools-3.4.1-11.el7.noarch
[root@localhost ~]# rpm -e --nodeps 1.7.0-openjdk-1.7.0.171-2.6.13.2.el7.x86_64
error: package 1.7.0-openjdk-1.7.0.171-2.6.13.2.el7.x86_64 is not installed
[root@localhost ~]# rpm -e --nodeps tzdata-java-2018c-1.el7.noarch
[root@localhost ~]# rpm -e --nodeps python-javapackages-3.4.1-11.el7.noarch
[root@localhost ~]# rpm -e --nodeps java-1.7.0-openjdk-1.7.0.171-2.6.13.2.el7.x86_64
[root@localhost ~]# rpm -e --nodeps java-1.8.0-openjdk-1.8.0.161-2.b14.el7.x86_64
[root@localhost ~]# rpm -e --nodeps java-1.7.0-openjdk-headless-1.7.0.171-2.6.13.2.el7.x86_64
[root@localhost ~]# rpm -e --nodeps javapackages-tools-3.4.1-11.el7.noarch
[root@localhost ~]# rpm -qa | grep java
[root@localhost ~]# cp /mnt/share/share/jdk-7u80-linux-x64.tar.gz /usr/local/
[root@localhost ~]# cd /usr/local
[root@localhost local]# tar -zxvf jdk-7u80-linux-x64.tar.gz

[root@localhost local]# vim /etc/profile

export JAVA_HOME=/usr/local/jdk1.7.0_80
export JRE_HOME=${JAVA_HOME}/jre
export CLASSPATH=.:${JAVA_HOME}/lib:${JRE_HOME}/lib:$CLASSPATH
export JAVA_PATH=${JAVA_HOME}/bin:${JRE_HOME}/bin
export PATH=$PATH:${JAVA_PATH}

[root@localhost local]# source /etc/profile
[root@localhost local]# ls
apr  apr-1.7.0  apr-1.7.0.tar.gz  bin  etc  games  include  jdk1.7.0_80  jdk-7u80-linux-x64.tar.gz  lib  lib64  libexec  sbin  share  src

[root@localhost local]# javac -version
javac 1.7.0_80

输入命令：sudo vim /etc/profile

输入命令后打开环境变量文件进行配置，按 i 建开始编辑，

SSH加固