Image not persist

I have a Image for user to show user profile picture. User can upload the image, which will store in the vaadin theme folder so to set with ThemeResource(). The first time when user upload the image, it works. But after user change to another picture, at the moment the image is changed but after user sign out and sign in again, the picture change to the previous picture. Check with firebug the image source is from  ../APP/connector/0/.. . The original file is store in
webapp\VAADIN\themes\mytheme\img\profile\41

Please do not upload any pictures to theme resource. That is completely wrong approach, at least, if your application is deployed as .war file, the theme storage is read-only. Please save your uploaded image to somewhere else(separate file storage, or, preferably, database), and make a special servlet for downloading images.