参考了网上的一些教程：
1.找到安装maven的路径
2.直接搜索settings.xml文件
3.我反正是找到两个这样的文件，一个在maven2目录下一个在maven3目录下，我把两个文件的内容都改成如下：
找到
然后把下面代码直接copy替换就好了
<mirrors>
<!-- mirror
| Specifies a repository mirror site to use instead of a given repository. The repository that
| this mirror serves has an ID that matches the mirrorOf element of this mirror. IDs are used
| for inheritance and direct lookup purposes, and must be unique across the set of mirrors.
|
<mirror>
<id>mirrorId</id>
<mirrorOf>repositoryId</mirrorOf>
<name>Human Readable Name for this Mirror.</name>
<url>http://my.repository.com/repo/path</url>
</mirror>
-->
<!-- <mirror> -->
<!-- <id>repo2</id> -->
<!-- <mirrorOf>central</mirrorOf> -->
<!-- <name>Human Readable Name for this Mirror.</name> -->
<!-- <url>http://repo2.maven.org/maven2/</url> -->
<!-- </mirror> -->
<mirror>
<!--This sends everything else to /public -->
<id>nexus</id>
<mirrorOf>*</mirrorOf>
<url>http://maven.aliyun.com/nexus/content/groups/public/</url>
</mirror>
<mirror>
<!--This is used to direct the public snapshots repo in the
profile below over to a different nexus group -->
<id>nexus-public-snapshots</id>
<mirrorOf>public-snapshots</mirrorOf>
<url>http://maven.aliyun.com/nexus/content/repositories/snapshots/</url>
</mirror>
</mirrors>
