http\://maven.aliyun.com/nexus/content/groups/public/.error=Could not transfer artifact org.apache.logging.log4j\:log4j-bom\:pom\:2.10.0 from/to alimaven (http\://maven.aliyun.com/nexus/content/groups/public/)\: Connect to maven.aliyun.com\:80 [maven.aliyun.com/59.110.251.4, maven.aliyun.com/59.110.251.11, maven.aliyun.com/59.110.251.9, maven.aliyun.com/182.92.29.13, maven.aliyun.com/182.92.29.53, maven.aliyun.com/59.110.251.10, maven.aliyun.com/59.110.251.12, maven.aliyun.com/182.92.29.16, maven.aliyun.com/182.92.29.54, maven.aliyun.com/182.92.29.40] failed\: Connection timed out\: connect
@default-http\://maven.aliyun.com/nexus/content/groups/public/.lastUpdated=1541730920432
下载jar包失败，正常情况只要你的浏览器可以访问到jar包或者pom文件，那么你的maven就一定可以下载，如果不可以下载一定是配置不正确。遇到这个问题怎么解决？检查你是不是代理上网。这个可以自行百度，一旦确认了是代理上网，那么就有的放矢了。修改自己的setting.xml文件，添加代理配置。
<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>
配置参数就是你代理上网的配置。bingo！