Java Desktop Client for Web App

We need to create a Java desktop application to allow document uploads to our web application. Note - in all cases where the Web App is required to do something - we will program that function. We require the Freelancer to only work on the Java component. The Java application will: 1) Allow the user to login to the Java App - The login will be authenticated via HTTP to our Web App 2) Show a 'virtual file system', showing the structure of the file system in the web application - The data for this file system will be returned from the web application via XML or JSON (we will provide this feed) - Ability to browse folders, close folders, have folders inside folders - Ability to create folders (Create request to be sent to the Web App) 3) Allow a user to upload a file into the virtual file system via 'drag and drop' - User shall drag and drop file from desktop into the Java app - The file upload would happen via POST to the web application - Web App will return a 'success'/'fail' message 4) Allow a user to open a file from the virtual file system - On 'double click' the file will be retrieved from the Web App, and streamed to the Java App - When loaded to a local cache, it will open on the users desktop - The app needs to launch the appropriate software for the file. eg: MS Word, Excel 5) When a user 'saves' the file, it shall save back to the Web App - So, if a user is in MS Word, Excel, it should save back to the Java App - The Java App will stream the file back to the Web App.