Probably the easiest way to understand the JAF is by looking at Windows Explorer.
Windows Explorer allows you to right-click on a file and select a command from the list associated with the file type.
The lists will differ from one computer to another.
When you click a command, Windows Explorer invokes the appropriate application and pass the reference to the right-clicked file.
You can use the JAF in a Java editor so that upon clicking a text file, the user will be presented with a command list and be able to select a command that will launch the application to handle the object.
You need to decide the supported types of objects and invoke appropriate JavaBeans that can handle each type of object.