Make a brief note:

Unsatisfied dependencyexception exception

*Why*

mapper.xml In the folder, I accidentally transposed several letters of a long word (because I use a laptop, sometimes I accidentally click on the touchpad)

*Solutions*

Because it was a mistake discovered in time, I went directly mapper.xml Folder Ctrl + Z recovered…

*Other solutions*

You may have changed a lot of content, many times Ctrl + Z is also very boring, and it is also a waste of energy and time. At this time: right click the project local history to select the version before the error