Centos system installation jdk tutorial (super detailed)

1. Uninstall the original jdk cleanly

rpm -qa | grep jdk

rpm -e --nodeps 要卸载的JDK

2. Upload JDK only to the server

1. Create a new java directory under usr

mkdir /usr/java

2. Unzip jdk to /usr/java

tar -zxvf 所要解压的文件名 -C /usr/java

3. Edit vi /etc/profile

vi /etc/profile

4. Add environment variables at the end 

export JAVA_HOME=/usr/local/jdk目录
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}

5. Refresh /etc/profile

source /etc/profile

6. Detect version

java -version

7. Soft connection

ln -s /path/to/java/bin/java /usr/local/bin/java