去/usr/local目录下面(可以打开Finder command+shift+G)，把解压出来的文件拷贝到这个目录下面
/usr/local/apache-maven-3.6.3
1、$ sudo vi ~/.bash_profile
添加如下配置：
JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home
export JAVA_HOME
M2_HOME=/usr/local/apache-maven-3.6.3
export M2_HOME
PATH=${PATH}:${JAVA_HOME}/bin:${M2_HOME}/bin
export PATH
2、配置了Java的环境变量，直接在后面添加M2_HOME变量即可。添加完后退出，并运行source ~/.bash_profile，使配置文件生效，然后运行mvn -v查看：
3、执行命令：mvn -v
Apache Maven 3.6.3 (cecedd343002696d0abb50b32b541b8a6ba2883f)
Maven home: /usr/local/apache-maven-3.6.3
Java version: 1.8.0_251, vendor: Oracle Corporation, runtime: /Library/Java/JavaVirtualMachines/jdk1.8.0_251.jdk/Contents/Home/jre
Default locale: zh_CN, platform encoding: UTF-8
OS name: "mac os x", version: "10.14.5", arch: "x86_64", family: "mac"