HeartRating A class for rating with a single degree of rating, "heart" vs "no heart". 
LibraryResult Result class to be used with ListenableFuture for asynchronous calls between MediaLibraryService.MediaLibrarySession and MediaBrowser
MediaBrowser Browses media content offered by a MediaLibraryService
MediaBrowser.BrowserCallback Callback to listen events from MediaLibraryService
MediaBrowser.Builder Builder for MediaBrowser
MediaConstants Media constants for sharing constants between media provider and consumer apps  
MediaController Allows an app to interact with an active MediaSession or a MediaSessionService which would provide MediaSession
MediaController.Builder Builder for MediaController
MediaController.ControllerCallback Interface for listening to change in activeness of the MediaSession
MediaController.PlaybackInfo Holds information about the way volume is handled for this session. 
MediaLibraryService Base class for media library services, which is the service containing MediaLibraryService.MediaLibrarySession
MediaLibraryService.LibraryParams Contains information that the library service needs to send to the client. 
MediaLibraryService.LibraryParams.Builder Builds a MediaLibraryService.LibraryParams
MediaLibraryService.MediaLibrarySession Session for the MediaLibraryService
MediaLibraryService.MediaLibrarySession.Builder Builder for MediaLibraryService.MediaLibrarySession
MediaLibraryService.MediaLibrarySession.MediaLibrarySessionCallback Callback for the MediaLibraryService.MediaLibrarySession