Linux实战---CentOS7下yum方式安装JDK1.8并配置环境变量

CentOS7下yum方式安装JDK1.8并配置环境变量

环境说明
Centos版本: CentOS Linux release 7.7.1908 (Core) 安装的时候选择的是Minimal Install
JDK 下载地址 https://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html

第一步：查看是否安装过JDK

# 查看当前是否安装了JDK，如果安装了就直接卸载，我安装的是Minimal版本，系统内没有安装JDK
[root@localhost ~]# rpm -qa | grep -i jdk

第二步：安装JDK

#查看有哪些Java版本
[root@localhost opt]# yum list java*
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
 yum list java* * base: mirror.lzu.edu.cn
 * extras: mirror.lzu.edu.cn
 * updates: mirror.bit.edu.cn
Available Packages
java-1.6.0-openjdk.x86_64                     1:1.6.0.41-1.13.13.1.el7_3 base   
java-1.6.0-openjdk-demo.x86_64                1:1.6.0.41-1.13.13.1.el7_3 base   
java-1.6.0-openjdk-devel.x86_64               1:1.6.0.41-1.13.13.1.el7_3 base   
java-1.6.0-openjdk-javadoc.x86_64             1:1.6.0.41-1.13.13.1.el7_3 base   
java-1.6.0-openjdk-src.x86_64                 1:1.6.0.41-1.13.13.1.el7_3 base   
java-1.7.0-openjdk.x86_64                     1:1.7.0.241-2.6.20.0.el7_7 updates
java-1.7.0-openjdk-accessibility.x86_64       1:1.7.0.241-2.6.20.0.el7_7 updates
java-1.7.0-openjdk-demo.x86_64                1:1.7.0.241-2.6.20.0.el7_7 updates
java-1.7.0-openjdk-devel.x86_64               1:1.7.0.241-2.6.20.0.el7_7 updates
java-1.7.0-openjdk-headless.x86_64            1:1.7.0.241-2.6.20.0.el7_7 updates
java-1.7.0-openjdk-javadoc.noarch             1:1.7.0.241-2.6.20.0.el7_7 updates
java-1.7.0-openjdk-src.x86_64                 1:1.7.0.241-2.6.20.0.el7_7 updates
java-1.8.0-openjdk.i686                       1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk.x86_64                     1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-accessibility.i686         1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-accessibility.x86_64       1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-accessibility-debug.i686   1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-accessibility-debug.x86_64 1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-debug.i686                 1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-debug.x86_64               1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-demo.i686                  1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-demo.x86_64                1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-demo-debug.i686            1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-demo-debug.x86_64          1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-devel.i686                 1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-devel.x86_64               1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-devel-debug.i686           1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-devel-debug.x86_64         1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-headless.i686              1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-headless.x86_64            1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-headless-debug.i686        1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-headless-debug.x86_64      1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-javadoc.noarch             1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-javadoc-debug.noarch       1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-javadoc-zip.noarch         1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-javadoc-zip-debug.noarch   1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-src.i686                   1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-src.x86_64                 1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-src-debug.i686             1:1.8.0.232.b09-0.el7_7    updates
java-1.8.0-openjdk-src-debug.x86_64           1:1.8.0.232.b09-0.el7_7    updates
java-11-openjdk.i686                          1:11.0.5.10-0.el7_7        updates
java-11-openjdk.x86_64                        1:11.0.5.10-0.el7_7        updates
java-11-openjdk-debug.i686                    1:11.0.5.10-0.el7_7        updates
java-11-openjdk-debug.x86_64                  1:11.0.5.10-0.el7_7        updates
java-11-openjdk-demo.i686                     1:11.0.5.10-0.el7_7        updates
java-11-openjdk-demo.x86_64                   1:11.0.5.10-0.el7_7        updates
java-11-openjdk-demo-debug.i686               1:11.0.5.10-0.el7_7        updates
java-11-openjdk-demo-debug.x86_64             1:11.0.5.10-0.el7_7        updates
java-11-openjdk-devel.i686                    1:11.0.5.10-0.el7_7        updates
java-11-openjdk-devel.x86_64                  1:11.0.5.10-0.el7_7        updates
java-11-openjdk-devel-debug.i686              1:11.0.5.10-0.el7_7        updates
java-11-openjdk-devel-debug.x86_64            1:11.0.5.10-0.el7_7        updates
java-11-openjdk-headless.i686                 1:11.0.5.10-0.el7_7        updates
java-11-openjdk-headless.x86_64               1:11.0.5.10-0.el7_7        updates
java-11-openjdk-headless-debug.i686           1:11.0.5.10-0.el7_7        updates
java-11-openjdk-headless-debug.x86_64         1:11.0.5.10-0.el7_7        updates
java-11-openjdk-javadoc.i686                  1:11.0.5.10-0.el7_7        updates
java-11-openjdk-javadoc.x86_64                1:11.0.5.10-0.el7_7        updates
java-11-openjdk-javadoc-debug.i686            1:11.0.5.10-0.el7_7        updates
java-11-openjdk-javadoc-debug.x86_64          1:11.0.5.10-0.el7_7        updates
java-11-openjdk-javadoc-zip.i686              1:11.0.5.10-0.el7_7        updates
java-11-openjdk-javadoc-zip.x86_64            1:11.0.5.10-0.el7_7        updates
java-11-openjdk-javadoc-zip-debug.i686        1:11.0.5.10-0.el7_7        updates
java-11-openjdk-javadoc-zip-debug.x86_64      1:11.0.5.10-0.el7_7        updates
java-11-openjdk-jmods.i686                    1:11.0.5.10-0.el7_7        updates
java-11-openjdk-jmods.x86_64                  1:11.0.5.10-0.el7_7        updates
java-11-openjdk-jmods-debug.i686              1:11.0.5.10-0.el7_7        updates
java-11-openjdk-jmods-debug.x86_64            1:11.0.5.10-0.el7_7        updates
java-11-openjdk-src.i686                      1:11.0.5.10-0.el7_7        updates
java-11-openjdk-src.x86_64                    1:11.0.5.10-0.el7_7        updates
java-11-openjdk-src-debug.i686                1:11.0.5.10-0.el7_7        updates
java-11-openjdk-src-debug.x86_64              1:11.0.5.10-0.el7_7        updates
java-atk-wrapper.i686                         0.30.4-5.el7               base   
java-atk-wrapper.x86_64                       0.30.4-5.el7               base   
java_cup.noarch                               1:0.11a-16.el7             base   
java_cup-javadoc.noarch                       1:0.11a-16.el7             base   
java_cup-manual.noarch                        1:0.11a-16.el7             base   
javacc.noarch                                 5.0-10.el7                 base   
javacc-demo.noarch                            5.0-10.el7                 base   
javacc-javadoc.noarch                         5.0-10.el7                 base   
javacc-manual.noarch                          5.0-10.el7                 base   
javacc-maven-plugin.noarch                    2.6-17.el7                 base   
javacc-maven-plugin-javadoc.noarch            2.6-17.el7                 base   
javamail.noarch                               1.4.6-8.el7                base   
javamail-javadoc.noarch                       1.4.6-8.el7                base   
javapackages-tools.noarch                     3.4.1-11.el7               base   
javassist.noarch                              3.16.1-10.el7              base   
javassist-javadoc.noarch                      3.16.1-10.el7              base   
#安装 JDK1.8   yum -y  install 会在Is this OK[y/d/N] 自动选择y
[root@localhost opt]yum install java-1.8.0-openjdk-* -y
Complete!
# 查看是否安装成功 ，显示下面结果 标识安装成功
[root@localhost opt]# java -version
openjdk version "1.8.0_232"
OpenJDK Runtime Environment (build 1.8.0_232-b09)
OpenJDK 64-Bit Server VM (build 25.232-b09, mixed mode)

第四步：配置环境变量

# jdk安装目录 /usr/lib/jvm
[root@localhost ~]# cd /usr/lib/jvm
[root@localhost lib]# ls
java 
java-1.8.0-openjdk 
java-1.8.0-openjdk-1.8.0.232.b09-0.el7_7.x86_64-debug  
jre       
jre-1.8.0-openjdk
jre-1.8.0-openjdk-1.8.0.232.b09-0.el7_7.x86_64-debug
java-1.8.0  
java-1.8.0-openjdk-1.8.0.232.b09-0.el7_7.x86_64 
java-openjdk
jre-1.8.0 
jre-1.8.0-openjdk-1.8.0.232.b09-0.el7_7.x86_64  jre-openjdk
#编辑配置文件
[root@localhost /]# vi /etc/profile
#文件底部添加如下代码
export JAVA_HOME=/usr/lib/jvm/java-1.8.0-openjdk-1.8.0.232.b09-0.el7_7.x86_64
export CLASSPATH=.:$JAVA_HOME/lib/dt.jar:$JAVA_HOME/lib/tools.jar
export PATH=$JAVA_HOME/bin:$PATH
#重启配置文件
[root@localhost /]# . /etc/profile