Problem: The eclipse project uses maven to download the dependency package, but sometimes it will not be downloaded automatically when the network is disconnected, which is very painful.
Therefore, we need to re-update the project download.
The first is to find in the setting.xml configuration under the maven conf file:
Find the warehouse address, my warehouse address is: D:\Repositories\maven
Then search for .lastUpdated in D:\Repositories\maven
Then delete the file of type LASTUPSATED
Finally, select the maven project, right-click maven->update project.
nailed it...