# java.util.prefs

Added in[API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels)  

# java.util.prefs

This package allows applications to store and retrieve user and system preference and configuration data. This data is stored persistently in an implementation-dependent backing store. There are two separate trees of preference nodes, one for user preferences and one for system preferences.

## Interfaces

|--------------------------------------------------------------------------------------------------------------|---------------------------------------------------------|
| [NodeChangeListener](https://developer.android.com/reference/java/util/prefs/NodeChangeListener)             | A listener for receiving preference node change events. |
| [PreferenceChangeListener](https://developer.android.com/reference/java/util/prefs/PreferenceChangeListener) | A listener for receiving preference change events.      |
| [PreferencesFactory](https://developer.android.com/reference/java/util/prefs/PreferencesFactory)             | A factory object that generates Preferences objects.    |

## Classes

|--------------------------------------------------------------------------------------------------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [AbstractPreferences](https://developer.android.com/reference/java/util/prefs/AbstractPreferences)     | This class provides a skeletal implementation of the[Preferences](https://developer.android.com/reference/java/util/prefs/Preferences)class, greatly easing the task of implementing it. |
| [NodeChangeEvent](https://developer.android.com/reference/java/util/prefs/NodeChangeEvent)             | An event emitted by aPreferencesnode to indicate that a child of that node has been added or removed.                                                                                    |
| [PreferenceChangeEvent](https://developer.android.com/reference/java/util/prefs/PreferenceChangeEvent) | An event emitted by aPreferencesnode to indicate that a preference has been added, removed or has had its value changed.                                                                 |
| [Preferences](https://developer.android.com/reference/java/util/prefs/Preferences)                     | A node in a hierarchical collection of preference data.                                                                                                                                  |

## Exceptions

|--------------------------------------------------------------------------------------------------------------------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| [BackingStoreException](https://developer.android.com/reference/java/util/prefs/BackingStoreException)                         | Thrown to indicate that a preferences operation could not complete because of a failure in the backing store, or a failure to contact the backing store.                                                                                                                   |
| [InvalidPreferencesFormatException](https://developer.android.com/reference/java/util/prefs/InvalidPreferencesFormatException) | Thrown to indicate that an operation could not complete because the input did not conform to the appropriate XML document type for a collection of preferences, as per the[Preferences](https://developer.android.com/reference/java/util/prefs/Preferences)specification. |

-

  ## Interfaces

  - [NodeChangeListener](https://developer.android.com/reference/java/util/prefs/NodeChangeListener)
  - [PreferenceChangeListener](https://developer.android.com/reference/java/util/prefs/PreferenceChangeListener)
  - [PreferencesFactory](https://developer.android.com/reference/java/util/prefs/PreferencesFactory)
-

  ## Classes

  - [AbstractPreferences](https://developer.android.com/reference/java/util/prefs/AbstractPreferences)
  - [NodeChangeEvent](https://developer.android.com/reference/java/util/prefs/NodeChangeEvent)
  - [PreferenceChangeEvent](https://developer.android.com/reference/java/util/prefs/PreferenceChangeEvent)
  - [Preferences](https://developer.android.com/reference/java/util/prefs/Preferences)
-

  ## Exceptions

  - [BackingStoreException](https://developer.android.com/reference/java/util/prefs/BackingStoreException)
  - [InvalidPreferencesFormatException](https://developer.android.com/reference/java/util/prefs/InvalidPreferencesFormatException)