原因:
maven更新项目后,导致
Deployment assembly 中 maven dependencies 丢失.解决方法:
I'm working with Eclipse and I had same problem every time I made changes in my pom.xml. I don't know why but Eclipse delete the Maven Dependencies.
Solution: rigth click on project, select Properties, choose Deployment Assembly and verify in column "Source" a row called "Maven Dependencies". If it isn't there, click on Add..., Java Build Path Entries and click on Maven Dependencies. Finally Apply and close.