Linux下安装Java

安装Java

[root@localhost ~]# yum -y list java*   ##查找java相关的列表
##安装jdk
[root@localhost ~]# yum -y install java-1.8.0-openjdk.x86_64     
##完成安装后验证
[root@localhost ~]# java -version   
openjdk version "1.8.0_242"
OpenJDK Runtime Environment (build 1.8.0_242-b08)
OpenJDK 64-Bit Server VM (build 25.242-b08, mixed mode)
##通过yum安装的默认路径为：/usr/lib/jvm
[root@localhost ~]# cd /usr/lib/jvm/   
[root@localhost jvm]# ls
java-1.8.0-openjdk-1.8.0.242.b08-0.el7_7.x86_64
jre
jre-1.8.0
jre-1.8.0-openjdk
jre-1.8.0-openjdk-1.8.0.242.b08-0.el7_7.x86_64
jre-openjdk
##配置Java变量环境，将jdk的安装路径加入到JAVA_HOME
[root@localhost jvm]# vi /etc/profile   
##在文件最后加入
JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.242.b08-0.el7_7.x86_64
JRE_HOME=$JAVA_HOME/jre
CLASS_PATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar:$JRE_HOME/lib
PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin
export JAVA_HOME JRE_HOME CLASS_PATH PATH
让文件生效（注：.后有一个空格）
[root@localhost ~]# . /etc/profile
测试
[root@localhost ~]# java -version
openjdk version "1.8.0_242"
OpenJDK Runtime Environment (build 1.8.0_242-b08)
OpenJDK 64-Bit Server VM (build 25.242-b08, mixed mode)