<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>alimaven</id>
<name>aliyun maven</name>
<url>http://maven.aliyun.com/nexus/content/groups/public/</url>
<mirrorOf>central</mirrorOf>
</mirror>
<mirror>
<id>uk</id>
<mirrorOf>central</mirrorOf>
<name>Human Readable Name for this Mirror.</name>
<url>http://uk.maven.org/maven2/</url>
</mirror>
<mirror>
<id>CN</id>
<name>OSChina Central</name>
<url>http://maven.oschina.net/content/groups/public/</url>
<mirrorOf>central</mirrorOf>
</mirror>
<mirror>
<id>nexus</id>
<name>internal nexus repository</name>
<!-- <url>http://192.168.1.100:8081/nexus/content/groups/public/</url>-->
<url>http://repo.maven.apache.org/maven2</url>
<mirrorOf>central</mirrorOf>
</mirror>
</mirrors>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.6.0</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
原文：http://www.cnblogs.com/empireghost/p/6305840.html