1.今天使用命令mvn compile编译maven项目时提示错误信息，部分错误信息如下：
Failure to transfer wsdl4j:wsdl4j:jar:1.6.3 from http://xx.xx.xx.xx:8081/nexus/content/groups/public was cached in the local repository, resolution will not be reattempted until the update interval of public has elapsed or updates are forced. Original error: Could not transfer artifact wsdl4j:wsdl4j:jar:1.6.3 from/to public (http://xx.xx.xx.xx:8081/nexus/content/groups/public): The operation was cancelled.
发现wsdl4j-1.6.3.jar下载到本地时失败，从提示可知是本地仓库的缓存（cached）造成。我们找到maven的仓库目录,找到该jar的下载目录。找到.lastUpdated文件，删除它。然后eclipse-->maven-->updateMaven,重新下载jar后。如果下载成功，那么这个错误就会消失。
2.MVN 构建项目时的一个问题--Could not resolve de pendencies for project
解决maven cannot change version of project facet dynamic web module to 3.0