http://www.cnblogs.com/geektown/p/5705405.html
D:\javaInstall\apache-maven-3.3.9-bin\apache-maven-3.3.9\conf\settings.xml
54行： <localRepository>D:\maven_repository</localRepository>
151行左右修改镜像，可以更快的下载jar包
<mirror>
<id>nexus-aliyun</id>
<mirrorOf>*</mirrorOf>
<name>Nexus aliyun</name>
<url>http://maven.aliyun.com/nexus/content/groups/public</url>
</mirror>
============要建一个本地仓库