The AssociationService class provides several methods to access the file type associations. It includes methods to retrieve a particular file type association, to register a new file type association into the system, and to unregister a registered file type association from the system. Each file type association is represented by an Association object.

The file type information storage and access mechanism is platform-dependent:

• For Microsoft Windows platforms, the file type information is stored in the registry, which is a tree structure.
• For Gnome/UNIX platforms, the file type information is stored in the MIME type database, which consists of some plain text files (.keys, .mime, .applications). Each MIME text file could contain one or multiple file types. A file type could be registered in the system by providing new MIME files, or being added to existing MIME files.