| NodeChangeListener | This interface is used to handle preference node change events. | 
| PreferenceChangeListener | This interface is used to handle preferences change events. | 
| PreferencesFactory | This interface is used by the Preferences class as factory class to
 create Preferences instances.  | 
          
| AbstractPreferences | This abstract class is a partial implementation of the abstract class
 Preferences, which can be used to simplify Preferences provider's
 implementation.  | 
          
| NodeChangeEvent | This is the event class to indicate that one child of the preference node has been added or deleted. | 
| PreferenceChangeEvent | This is the event class to indicate that a preference has been added, deleted or updated. | 
| Preferences | An instance of the class Preferences represents one node in a
 preference tree, which provides a mechanism to store and access configuration
 data in a hierarchical way.  | 
          
| BackingStoreException | An exception to indicate that an error was encountered while accessing the backing store. | 
| InvalidPreferencesFormatException | An exception to indicate that the input XML file is not well-formed or could
 not be validated against the appropriate document type (specified by
 in the Preferences).  |