我们的编译服务器不能直接访问公网，那么Maven如何使用代理访问公网？

     | Specification for one proxy, to be used in connecting to the network.

     |

    <proxy>

      <id>optional</id>

      <active>true</active>

      <protocol>http</protocol>

      <username>proxyuser</username>

      <password>proxypass</password>

      <host>proxy.host.net</host>

      <port>80</port>

      <nonProxyHosts>local.net|some.host.com</nonProxyHosts>

    </proxy>

    -->

    <proxy>

      <id>optional</id>  <!--代理服务器ID，可随意命名-->

      <active>true</active>  <!-- 是否启用 -->

      <protocol>http</protocol>  <!-- 通信协议 -->

      <username></username> <!-- 代理服务器用户名，无则不填 -->

      <password></password>  <!-- 代理服务器密码，无则不填 -->

      <host>10.1.56.203</host>   <!-- 代理服务器主机地址 -->

      <port>3128</port>  <!-- 通信端口 -->

      <nonProxyHosts></nonProxyHosts>   <!—局域网内不需要通过代理的服务器，多个地址用“|”分隔 -->

    </proxy>

  </proxies>

      <id>jboss-public-repository-group</id>

      <name>JBoss Public Maven Repository Group</name>

      <url>https://repository.jboss.org/nexus/content/groups/public/</url>

      <layout>default</layout>

      <releases>

        <enabled>true</enabled>

        <updatePolicy>never</updatePolicy>

      </releases>

      <snapshots>

        <enabled>true</enabled>

        <updatePolicy>never</updatePolicy>

      </snapshots>

    </repository>