maven error ’failed to collect dependencies’

[Switch]
Recently upgraded springframework version (3.1.2->3.2.5), when printing version dependencies, an error
'failed to collect dependencies' is reported. I know it is a dependency problem, but I don't know how to solve it. Baidu took a look and solved it in the following way:
mvn dependency:tree > tree.txt -U -Dmaven.test.skip=true
-U,--update-snapshots Forces a check for updated releases and snapshots on remote.

The initial analysis may be that there is a problem with the local maven repo, through -U The command forces the relevant dependencies to be re-downloaded from the remote warehouse. If there are many unit test errors in the project, you can add -Dmaven.test.skip=true.