Get DataObject icon

We can register a new File Type for a new file extension or xml namespace, so in that way we can define a new mimeType and iconBase for our file. Now I need to select that file, and get it's registered icon(for example as a property of other file type):


Code:
File file = fileChooser.getSelectedFile();
DataObject dataObject = DataObject.find(FileUtil.toFileObject(file));



How I can get the registered icon for this DataObject, asuming that it exist?
There is any way of only select files inside my projects and not in the entire file system?

Thanks