一、安装JDK并配置环境变量

将JDK的安装包上传到Linux系统的usr/local目录
使用xftp上传文件

解压JDK的压缩包
xshell连接到云主机

[root@theo ~]# cd /usr/local

[root@theo local]# ls
aegis  apache-tomcat-8.5.46.tar.gz  bin  etc  games  include  jdk-8u221-linux-x64.tar.gz  lib  lib64  libexec  sbin  share  src

[root@theo local]# tar -zxvf jdk-8u221-linux-x64.tar.gz

查看解压后的目录结构

[root@theo local]# ls
aegis  apache-tomcat-8.5.46.tar.gz  bin  etc  games  include  jdk1.8.0_221  jdk-8u221-linux-x64.tar.gz  lib  lib64  libexec  sbin  share  src

[root@theo local]# cd jdk1.8.0_221/
[root@theo jdk1.8.0_221]# ls
bin  COPYRIGHT  include  javafx-src.zip  jre  lib  LICENSE  man  README.html  release  src.zip  THIRDPARTYLICENSEREADME-JAVAFX.txt  THIRDPARTYLICENSEREADME.txt

[root@theo jdk1.8.0_221]# cd bin
[root@theo bin]# ls
appletviewer  jar        javadoc         javapackager  jconsole  jhat   jmc         jsadebugd  jvisualvm     pack200     rmiregistry  tnameserv  xjc
ControlPanel  jarsigner  javafxpackager  java-rmi.cgi  jcontrol  jinfo  jmc.ini     jstack     keytool       policytool  schemagen    unpack200
extcheck      java       javah           javaws        jdb       jjs    jps         jstat      native2ascii  rmic        serialver    wsgen
idlj          javac      javap           jcmd          jdeps     jmap   jrunscript  jstatd     orbd          rmid        servertool   wsimport

配置jdk环境
进入到/etc目录，找到profile文件

[root@theo bin]# cd /etc
[root@theo etc]# ls

编辑这个profile文件，在文件中添加JDK环境变量
vim profile

[root@theo etc]# vim profile  可以打开文件编辑器，必须输入字母i进入到编辑状态,在最后面添加如下四项配置

export JAVA_HOME=/usr/local/jdk1.8.0_221
export JRE_HOME=$JAVA_HOME/jre
export CLASSPATH=.:$JAVA_HOME/lib:$JRE_HOME/lib
export PATH=$JAVA_HOME/bin:$PATH

编辑完成之后，点击键盘“Esc”按键退出编辑状态，输入:wq保存并退出编辑器

重新加载配置文件查看java版本

[root@theo etc]# source /etc/profile

[root@theo etc]# java -version
java version "1.8.0_221"
Java(TM) SE Runtime Environment (build 1.8.0_221-b11)
Java HotSpot(TM) 64-Bit Server VM (build 25.221-b11, mixed mode)

二、安装maven并配置环境变量

准备maven的压缩包

apache-maven-3.6.3-bin.tar.gz

解压到opt文件夹下

[root@iZ2ze6psmhg970tbycgrbpZ ~]# tar -zxvf apache-maven-3.6.3-bin.tar.gz -C /opt/

进入opt文件夹查看解压文件

[root@iZ2ze6psmhg970tbycgrbpZ ~]# cd /opt/
[root@iZ2ze6psmhg970tbycgrbpZ opt]# ls
apache-maven-3.6.3
[root@iZ2ze6psmhg970tbycgrbpZ opt]# 

重命名文件夹
重命名为maven

[root@iZ2ze6psmhg970tbycgrbpZ opt]# mv apache-maven-3.6.3/ maven
[root@iZ2ze6psmhg970tbycgrbpZ opt]# ls
maven

配置环境变量
vim /etc/profile
键盘 i 进行编辑，在最后加入maven环境配置

export MAVEN_HOME=/opt/maven
export PATH=$PATH:$MAVEN_HOME/bin

：wq退出编辑文件
source /etc/profile 使文件配置生效
检查maven是否配置成功

[root@iZ2ze6psmhg970tbycgrbpZ opt]# mvn -vesion
Apache Maven 3.6.3 (cecedd343002696d0abb50b32b541b8a6ba2883f)
Maven home: /opt/maven
Java version: 1.8.0_221, vendor: Oracle Corporation, runtime: /usr/local/jdk1.8.0_221/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "linux", version: "5.10.134-15.al8.x86_64", arch: "amd64", family: "unix"

配置maven阿里云镜像
编辑settings.xml文件

vim /opt/maven/conf/settings.xml

在mirrors标签中间加入mirror镜像标签

	<mirror>
		<id>alimaven</id>
		<mirrorOf>central</mirrorOf>
		<name>aliyun maven</name>
		<url>http://maven.aliyun.com/nexus/content/repositories/central/</url>
	</mirror>
	<mirror>
		<id>nexus-alimaven</id>
		<mirrorOf>*,!jeecg,!jeecg-snapshots</mirrorOf>
		<name>Nexus aliyun</name>
		<url>http://maven.aliyun.com/nexus/content/groups/public/</url>
	</mirror>