@JeffryBooher `handleFileClose` is also having prompt. If i move prompt code from `handleFileCloseAll` to `DocumentManager.closeDocuments`, we will have prompt code in two different files (DocumentManager and DocumentCommandHandler) for the same functionality.

In this case, we should make `handleFileClose` and `handleFileCloseAll` to single function with file array as input param. Something like this.

    //this function will do both 'handleFileClose' and 'handleFileCloseAll' functionalities
    function handleFileClose(files) {
             DocumentManager.closeDocuments(files);
    }  

    function DocumentManager.closeDocuments(files) {

            var dirtyFiles = getDirtyFiles(files);

            if(dirtyFiles.length === 1) {
                     //prompt for single file.
            } else {
                     //prompt for multiple files.
            }

    }

But again to save documents i have to refer `handleFileSave` in `DocumentCommandHandler`. 

Another biggest problem here, `handleFileClose` and `handleFileCloseAll` are referred by many files. So eventually we have to change them all. So it may seems like biggest change. But at the end, we will have good code. What do you think?