idea maven import时出现这个错误，不管怎么加载，部分jar包就是下载不了；这个问题排查下来应该是网络问题。

方法一：可以换个网络重新import,比如换成手机热点。不过我出现这个问题的原因就是因为使用手机热点。换成网线就正常了。
方法二：可以在settings.xml文件换个镜像地址;换成下面的settings.xml重新导入就可以了。

<?xml version="1.0" encoding="UTF-8"?>
<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>D:\maven</localRepository>
    <localRepository>C:\Users\Chenqi\.m2\repository</localRepository>-->
<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://repo.maven.apache.org/maven2</url>
    <mirrorOf>central</mirrorOf>
  </mirror>

</mirrors>
</settings>