[Eclipse] Fixing: resource is out of sync

Sometimes when we try to synchronize with the cvs repository, we hit an error like this:

Resource is out of sync with the file system: filename

It's due to the changes outside can't be recognized by Eclipse. To fix this, we simply need to refresh the project (right click and select refresh)

To achieve the automatic synchronization with the file system, we can modify the preference like this:

Window -> Preferences -> General -> Workspace

select Refresh automatically.