maven缺少依赖包，强制更新命令

mvn clean install -e -U

-e详细异常，-U强制更新 

If your local repository is somehow mucked up for release jars as opposed to snapshots (-U and --update-snapshots only update snapshots), you can purge the local repo using the following:

                       mvn dependency:purge-local-repository

You probably then want to clean and install again:

                       mvn dependency:purge-local-repository clean install

Just in case someone wants only update project‘s snapshot dependencies and doesn‘t want to install artifact:

            mvn dependency:resolve -U 

Don‘t forget to reimport dependencies in your IDE. In IDEA you need to right click on pom file and choose Maven -> Reimport

原文：http://www.cnblogs.com/javabg/p/7603811.html