Problem description:
j2ee web debugging process I found that no matter how I modified it did not change, and then I clean it, but after this program can not run, 404 can not find resources.

Reason analysis:
checked the path of the release project
controller in classes these folders are all directories, no files, after searching baidu, it should be a reference project lack of jar package, leading to the project build failure, but the empty directory was built, leading to this problem.

Solutions:
once I know what the problem is, I remove the jar from the path and add it again, and the project runs.