Centos Linux JAVA installation configuration

Clear the built-in java-related packages

1. Query the open-jdk and other java-related packages that come with Centos

   rpm -qa|grep java

2. uninstall these packages

   # yum -y remove 软件包
   yum -y remove java-1.8.0-openjdk-headless-1.8.0.102-4.b14.el7.x86_64 java-1.7.0-openjdk-headless-1.7.0.111-2.6.7.8.el7.x86_64 tzdata-java-2016g-2.el7.noarch python-javapackages-3.4.1-11.el7.noarch java-1.8.0-openjdk-1.8.0.102-4.b14.el7.x86_64 javapackages-tools-3.4.1-11.el7.noarch java-1.7.0-openjdk-1.7.0.111-2.6.7.8.el7.x86_64

3. After uninstalling, check whether the java version can be found. If no version prompt is found, the uninstallation is clean.

   java -version

Install the uploaded JAVA package

1. move java package

   cd java包的文件夹
   # mv 命令 移动文件 
   mv jdk-8u202-linux-x64.tar.gz /usr/local/src/
   cd /usr/local/src

2. Unzip the compressed package

   tar -zxvf jdk-8u202-linux-x64.tar.gz
   ​
   # mv 重命名 
   mv jdk1.8.0_202/ jdk8

Configure environment variables

1. Modify global environment variables (not a single user)

   # 全局环境变量->/etc/profile 个用户环境变量-> ~/.bashrc
   vi /etc/profile

   #JAVA
   JAVA_HOME=/usr/local/src/jdk8
   JRE_HOME=$JAVA_HOME/jre
   PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin
   CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar:$JRE_HOME/lib
   export JAVA_HOME JRE_HOME PATH

2. Refresh configuration file

   source /etc/profile

   • Check whether java is configured successfully

     java -version

     If you can successfully see the version, you will be successful

send to other computer

scp -r /usr/local/src/jdk8 192.168.136.135:/usr/local/src 

Modify the configuration file