以往来说我们maven换源是改conf文件夹下的settings.xml。
百度的资料是在加一个仓库，但是往往没有。在各种资料之下，发现一个好用的。我们直接吧settings的内容全部替换. 以下是阿里云的仓库

<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
                      http://maven.apache.org/xsd/settings-1.0.0.xsd">
  <localRepository/>
  <interactiveMode/>
  <usePluginRegistry/>
  <offline/>
  <pluginGroups/>
  <servers/>
  <mirrors>
    <mirror>
     <id>aliyunmaven</id>
     <mirrorOf>central</mirrorOf>
     <name>阿里云公共仓库</name>
     <url>https://maven.aliyun.com/repository/central</url>
    </mirror>
    <mirror>
      <id>repo1</id>
      <mirrorOf>central</mirrorOf>
      <name>central repo</name>
      <url>http://repo1.maven.org/maven2/</url>
    </mirror>
    <mirror>
     <id>aliyunmaven</id>
     <mirrorOf>apache snapshots</mirrorOf>
     <name>阿里云阿帕奇仓库</name>
     <url>https://maven.aliyun.com/repository/apache-snapshots</url>
    </mirror>
  </mirrors>
  <proxies/>
  <activeProfiles/>
  <profiles>
    <profile>  
        <repositories>
           <repository>
                <id>aliyunmaven</id>
                <name>aliyunmaven</name>
                <url>https://maven.aliyun.com/repository/public</url>
                <layout>default</layout>
                <releases>
                        <enabled>true</enabled>
                </releases>
                <snapshots>
                        <enabled>true</enabled>
                </snapshots>
            </repository>
            <repository>
                <id>MavenCentral</id>
                <url>http://repo1.maven.org/maven2/</url>
            </repository>
            <repository>
                <id>aliyunmavenApache</id>
                <url>https://maven.aliyun.com/repository/apache-snapshots</url>
            </repository>
        </repositories>             
     </profile>
  </profiles>
</settings>