Maven 是一个项目管理工具，可以对 Java 项目进行构建、依赖管理。
参看这里：https://www.runoob.com/maven/maven-setup.html

Maven 阿里云镜像服务

https://maven.aliyun.com/mvn/guide

~/.m2/settings.xml

<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 https://maven.apache.org/xsd/settings-1.0.0.xsd">
    <localRepository />
    <interactiveMode />
    <offline />
    <pluginGroups />
    <servers />
    <mirrors>
        <mirror>
            <id>aliyunmaven</id>
            <mirrorOf>*</mirrorOf>
            <name>阿里云公共仓库</name>
            <url>https://maven.aliyun.com/repository/public</url>
        </mirror>
    </mirrors>
    <proxies />
    <profiles />
    <activeProfiles />
</settings>