http://books.sonatype.com/nexus-book/reference/confignx-sect-manage-repo.html
Public Repositories
对外地址
http://192.168.0.244:8081/nexus/content/groups/public/
Group ID
Publis URL
例如：
http://repo.maven.apache.org/maven2/
http://repo1.maven.org/maven2/
https://repository.apache.org/content/groups/public/
https://oss.sonatype.org/content/repositories/releases/
http://repo.spring.io/release/
http://maven.oschina.net/content/groups/public/
http://repository.ow2.org/nexus/content/repositories/snapshots/
http://repository.apache.org/snapshots/
https://oss.sonatype.org/content/repositories/snapshots/
https://nexus.codehaus.org/snapshots/
标红的是nexus默认的三个代理
代理
代理仓库一开始给了3个
有Apache 、Codehaus 和 maven中央仓库
可以仿照这个添加其他代理
宿主
3rd Party
This hosted repository should be used for third-party dependencies not available in the public Maven repositories. Examples of these dependencies could be commercial, proprietary libraries such as an Oracle JDBC driver that may be referenced by your organization.
Releases
This hosted repository is where your organization will publish internal releases.
Snapshots
This hosted repository is where your organization will publish internal snapshots.
商业和具有版权的不允许随意传播的，购买了使用权的，放到3rd Party
自己的快照放到Snapshots
自己的发布版放到Releases
Virtual Repository
expose any repository format
适配除了maven2以外的仓库