IT. Expert System.

public class Environment
extends Object

• Nested Class Summary

  Nested Classes

  Modifier and Type	Class and Description
  static class	Environment.UserEnvironment

• Field Summary

  Fields

  Modifier and Type	Field and Description
  static String	DIRECTORY_ALARMS Standard directory in which to place any audio files that should be in the list of alarms that the user can select (not as regular music).
  static String	DIRECTORY_ANDROID
  static String	DIRECTORY_DCIM The traditional location for pictures and videos when mounting the device as a camera.
  static String	DIRECTORY_DOWNLOADS Standard directory in which to place files that have been downloaded by the user.
  static String	DIRECTORY_MOVIES Standard directory in which to place movies that are available to the user.
  static String	DIRECTORY_MUSIC Standard directory in which to place any audio files that should be in the regular list of music for the user.
  static String	DIRECTORY_NOTIFICATIONS Standard directory in which to place any audio files that should be in the list of notifications that the user can select (not as regular music).
  static String	DIRECTORY_PICTURES Standard directory in which to place pictures that are available to the user.
  static String	DIRECTORY_PODCASTS Standard directory in which to place any audio files that should be in the list of podcasts that the user can select (not as regular music).
  static String	DIRECTORY_RINGTONES Standard directory in which to place any audio files that should be in the list of ringtones that the user can select (not as regular music).
  static String	MEDIA_BAD_REMOVAL getExternalStorageState() returns MEDIA_BAD_REMOVAL if the media was removed before it was unmounted.
  static String	MEDIA_CHECKING getExternalStorageState() returns MEDIA_CHECKING if the media is present and being disk-checked
  static String	MEDIA_MOUNTED getExternalStorageState() returns MEDIA_MOUNTED if the media is present and mounted at its mount point with read/write access.
  static String	MEDIA_MOUNTED_READ_ONLY getExternalStorageState() returns MEDIA_MOUNTED_READ_ONLY if the media is present and mounted at its mount point with read only access.
  static String	MEDIA_NOFS getExternalStorageState() returns MEDIA_NOFS if the media is present but is blank or is using an unsupported filesystem
  static String	MEDIA_REMOVED getExternalStorageState() returns MEDIA_REMOVED if the media is not present.
  static String	MEDIA_SHARED getExternalStorageState() returns MEDIA_SHARED if the media is present not mounted, and shared via USB mass storage.
  static String	MEDIA_UNMOUNTABLE getExternalStorageState() returns MEDIA_UNMOUNTABLE if the media is present but cannot be mounted.
  static String	MEDIA_UNMOUNTED getExternalStorageState() returns MEDIA_UNMOUNTED if the media is present but not mounted.

• Constructor Summary

  Constructors

  Constructor and Description
  Environment()

• Method Summary

  Methods

  Modifier and Type	Method and Description
  static File	getDataDirectory() Gets the Android data directory.
  static File	getDownloadCacheDirectory() Gets the Android download/cache content directory.
  static File	getEmulatedStorageObbSource()
  static File	getEmulatedStorageSource(int userId)
  static File	getExternalStorageAndroidDataDir() Returns the path for android-specific data on the SD card.
  static File	getExternalStorageAppCacheDirectory(String packageName) Generates the path to an application's cache.
  static File	getExternalStorageAppDataDirectory(String packageName) Generates the raw path to an application's data
  static File	getExternalStorageAppFilesDirectory(String packageName) Generates the path to an application's files.
  static File	getExternalStorageAppMediaDirectory(String packageName) Generates the raw path to an application's media
  static File	getExternalStorageAppObbDirectory(String packageName) Generates the raw path to an application's OBB files
  static File	getExternalStorageDirectory() Gets the Android external storage directory.
  static File	getExternalStoragePublicDirectory(String type) Get a top-level public external storage directory for placing files of a particular type.
  static String	getExternalStorageState() Gets the current state of the primary "external" storage device.
  static File	getLegacyExternalStorageDirectory()
  static File	getLegacyExternalStorageObbDirectory()
  static File	getMediaStorageDirectory() Return directory used for internal media storage, which is protected by android.Manifest.permission#WRITE_MEDIA_STORAGE.
  static File	getRootDirectory() Gets the Android root directory.
  static File	getSecureDataDirectory() Gets the data directory for secure storage.
  static File	getSystemSecureDirectory() Gets the system directory available for secure storage.
  static File	getUserSystemDirectory(int userId) Return the system directory for a user.
  static void	initForCurrentUser()
  static boolean	isEncryptedFilesystemEnabled() Returns whether the Encrypted File System feature is enabled on the device or not.
  static boolean	isExternalStorageEmulated() Returns whether the device has an external storage device which is emulated.
  static boolean	isExternalStorageRemovable() Returns whether the primary "external" storage device is removable.

  • Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

• Field Detail

  • DIRECTORY_ANDROID

    public static String DIRECTORY_ANDROID

  • DIRECTORY_MUSIC

    public static String DIRECTORY_MUSIC

    Standard directory in which to place any audio files that should be in the regular list of music for the user. This may be combined with DIRECTORY_PODCASTS, DIRECTORY_NOTIFICATIONS, DIRECTORY_ALARMS, and DIRECTORY_RINGTONES as a series of directories to categories a particular audio file as more than one type.

  • DIRECTORY_PODCASTS

    public static String DIRECTORY_PODCASTS

    Standard directory in which to place any audio files that should be in the list of podcasts that the user can select (not as regular music). This may be combined with DIRECTORY_MUSIC, DIRECTORY_NOTIFICATIONS, DIRECTORY_ALARMS, and DIRECTORY_RINGTONES as a series of directories to categories a particular audio file as more than one type.

  • DIRECTORY_RINGTONES

    public static String DIRECTORY_RINGTONES

    Standard directory in which to place any audio files that should be in the list of ringtones that the user can select (not as regular music). This may be combined with DIRECTORY_MUSIC, DIRECTORY_PODCASTS, DIRECTORY_NOTIFICATIONS, and DIRECTORY_ALARMS as a series of directories to categories a particular audio file as more than one type.

  • DIRECTORY_ALARMS

    public static String DIRECTORY_ALARMS

    Standard directory in which to place any audio files that should be in the list of alarms that the user can select (not as regular music). This may be combined with DIRECTORY_MUSIC, DIRECTORY_PODCASTS, DIRECTORY_NOTIFICATIONS, and DIRECTORY_RINGTONES as a series of directories to categories a particular audio file as more than one type.

  • DIRECTORY_NOTIFICATIONS

    public static String DIRECTORY_NOTIFICATIONS

    Standard directory in which to place any audio files that should be in the list of notifications that the user can select (not as regular music). This may be combined with DIRECTORY_MUSIC, DIRECTORY_PODCASTS, DIRECTORY_ALARMS, and DIRECTORY_RINGTONES as a series of directories to categories a particular audio file as more than one type.

  • DIRECTORY_PICTURES

    public static String DIRECTORY_PICTURES

    Standard directory in which to place pictures that are available to the user. Note that this is primarily a convention for the top-level public directory, as the media scanner will find and collect pictures in any directory.

  • DIRECTORY_MOVIES

    public static String DIRECTORY_MOVIES

    Standard directory in which to place movies that are available to the user. Note that this is primarily a convention for the top-level public directory, as the media scanner will find and collect movies in any directory.

  • DIRECTORY_DOWNLOADS

    public static String DIRECTORY_DOWNLOADS

    Standard directory in which to place files that have been downloaded by the user. Note that this is primarily a convention for the top-level public directory, you are free to download files anywhere in your own private directories. Also note that though the constant here is named DIRECTORY_DOWNLOADS (plural), the actual file name is non-plural for backwards compatibility reasons.

  • DIRECTORY_DCIM

    public static String DIRECTORY_DCIM

    The traditional location for pictures and videos when mounting the device as a camera. Note that this is primarily a convention for the top-level public directory, as this convention makes no sense elsewhere.

  • MEDIA_REMOVED

    public static final String MEDIA_REMOVED

    getExternalStorageState() returns MEDIA_REMOVED if the media is not present.

    See Also:

    Constant Field Values

  • MEDIA_UNMOUNTED

    public static final String MEDIA_UNMOUNTED

    getExternalStorageState() returns MEDIA_UNMOUNTED if the media is present but not mounted.

    See Also:

    Constant Field Values

  • MEDIA_CHECKING

    public static final String MEDIA_CHECKING

    getExternalStorageState() returns MEDIA_CHECKING if the media is present and being disk-checked

    See Also:

    Constant Field Values

  • MEDIA_NOFS

    public static final String MEDIA_NOFS

    getExternalStorageState() returns MEDIA_NOFS if the media is present but is blank or is using an unsupported filesystem

    See Also:

    Constant Field Values

  • MEDIA_MOUNTED

    public static final String MEDIA_MOUNTED

    getExternalStorageState() returns MEDIA_MOUNTED if the media is present and mounted at its mount point with read/write access.

    See Also:

    Constant Field Values

  • MEDIA_MOUNTED_READ_ONLY

    public static final String MEDIA_MOUNTED_READ_ONLY

    getExternalStorageState() returns MEDIA_MOUNTED_READ_ONLY if the media is present and mounted at its mount point with read only access.

    See Also:

    Constant Field Values

  • MEDIA_SHARED

    public static final String MEDIA_SHARED

    getExternalStorageState() returns MEDIA_SHARED if the media is present not mounted, and shared via USB mass storage.

    See Also:

    Constant Field Values

  • MEDIA_BAD_REMOVAL

    public static final String MEDIA_BAD_REMOVAL

    getExternalStorageState() returns MEDIA_BAD_REMOVAL if the media was removed before it was unmounted.

    See Also:

    Constant Field Values

  • MEDIA_UNMOUNTABLE

    public static final String MEDIA_UNMOUNTABLE

    getExternalStorageState() returns MEDIA_UNMOUNTABLE if the media is present but cannot be mounted. Typically this happens if the file system on the media is corrupted.

    See Also:

    Constant Field Values

• Constructor Detail

  • Environment

    public Environment()

• Method Detail

  • initForCurrentUser

    public static void initForCurrentUser()

  • getRootDirectory

    public static File getRootDirectory()

    Gets the Android root directory.

  • getSystemSecureDirectory

    public static File getSystemSecureDirectory()

    Gets the system directory available for secure storage. If Encrypted File system is enabled, it returns an encrypted directory (/data/secure/system). Otherwise, it returns the unencrypted /data/system directory.

    Returns:

    File object representing the secure storage system directory.

  • getSecureDataDirectory

    public static File getSecureDataDirectory()

    Gets the data directory for secure storage. If Encrypted File system is enabled, it returns an encrypted directory (/data/secure). Otherwise, it returns the unencrypted /data directory.

    Returns:

    File object representing the data directory for secure storage.

  • getMediaStorageDirectory

    public static File getMediaStorageDirectory()

    Return directory used for internal media storage, which is protected by android.Manifest.permission#WRITE_MEDIA_STORAGE.

  • getUserSystemDirectory

    public static File getUserSystemDirectory(int userId)

    Return the system directory for a user. This is for use by system services to store files relating to the user. This directory will be automatically deleted when the user is removed.

  • isEncryptedFilesystemEnabled

    public static boolean isEncryptedFilesystemEnabled()

    Returns whether the Encrypted File System feature is enabled on the device or not.

    Returns:

    true if Encrypted File System feature is enabled, false if disabled.

  • getDataDirectory

    public static File getDataDirectory()

    Gets the Android data directory.

  • getExternalStorageDirectory

    public static File getExternalStorageDirectory()

    Gets the Android external storage directory. This directory may not currently be accessible if it has been mounted by the user on their computer, has been removed from the device, or some other problem has happened. You can determine its current state with getExternalStorageState().

    Note: don't be confused by the word "external" here. This directory can better be thought as media/shared storage. It is a filesystem that can hold a relatively large amount of data and that is shared across all applications (does not enforce permissions). Traditionally this is an SD card, but it may also be implemented as built-in storage in a device that is distinct from the protected internal storage and can be mounted as a filesystem on a computer.

    On devices with multiple users (as described by UserManager), each user has their own isolated external storage. Applications only have access to the external storage for the user they're running as.

    In devices with multiple "external" storage directories (such as both secure app storage and mountable shared storage), this directory represents the "primary" external storage that the user will interact with.

    Applications should not directly use this top-level directory, in order to avoid polluting the user's root namespace. Any files that are private to the application should be placed in a directory returned by Context.getExternalFilesDir, which the system will take care of deleting if the application is uninstalled. Other shared files should be placed in one of the directories returned by getExternalStoragePublicDirectory(java.lang.String).

    Writing to this path requires the android.Manifest.permission#WRITE_EXTERNAL_STORAGE permission. In a future platform release, access to this path will require the android.Manifest.permission#READ_EXTERNAL_STORAGE permission, which is automatically granted if you hold the write permission.

    This path may change between platform versions, so applications should only persist relative paths.

    Here is an example of typical code to monitor the state of external storage:

    See Also:

    getExternalStorageState(), isExternalStorageRemovable()

  • getLegacyExternalStorageDirectory

    public static File getLegacyExternalStorageDirectory()

  • getLegacyExternalStorageObbDirectory

    public static File getLegacyExternalStorageObbDirectory()

  • getEmulatedStorageSource

    public static File getEmulatedStorageSource(int userId)

  • getEmulatedStorageObbSource

    public static File getEmulatedStorageObbSource()

  • getExternalStoragePublicDirectory

    public static File getExternalStoragePublicDirectory(String type)

    Get a top-level public external storage directory for placing files of a particular type. This is where the user will typically place and manage their own files, so you should be careful about what you put here to ensure you don't erase their files or get in the way of their own organization.

    On devices with multiple users (as described by UserManager), each user has their own isolated external storage. Applications only have access to the external storage for the user they're running as.

    Here is an example of typical code to manipulate a picture on the public external storage:

    Parameters:

    type - The type of storage directory to return. Should be one of DIRECTORY_MUSIC, DIRECTORY_PODCASTS, DIRECTORY_RINGTONES, DIRECTORY_ALARMS, DIRECTORY_NOTIFICATIONS, DIRECTORY_PICTURES, DIRECTORY_MOVIES, DIRECTORY_DOWNLOADS, or DIRECTORY_DCIM. May not be null.

    Returns:

    Returns the File path for the directory. Note that this directory may not yet exist, so you must make sure it exists before using it such as with File.mkdirs().

  • getExternalStorageAndroidDataDir

    public static File getExternalStorageAndroidDataDir()

    Returns the path for android-specific data on the SD card.

  • getExternalStorageAppDataDirectory

    public static File getExternalStorageAppDataDirectory(String packageName)

    Generates the raw path to an application's data

  • getExternalStorageAppMediaDirectory

    public static File getExternalStorageAppMediaDirectory(String packageName)

    Generates the raw path to an application's media

  • getExternalStorageAppObbDirectory

    public static File getExternalStorageAppObbDirectory(String packageName)

    Generates the raw path to an application's OBB files

  • getExternalStorageAppFilesDirectory

    public static File getExternalStorageAppFilesDirectory(String packageName)

    Generates the path to an application's files.

  • getExternalStorageAppCacheDirectory

    public static File getExternalStorageAppCacheDirectory(String packageName)

    Generates the path to an application's cache.

  • getDownloadCacheDirectory

    public static File getDownloadCacheDirectory()

    Gets the Android download/cache content directory.

  • getExternalStorageState

    public static String getExternalStorageState()

    Gets the current state of the primary "external" storage device.

    See Also:

    getExternalStorageDirectory()

  • isExternalStorageRemovable

    public static boolean isExternalStorageRemovable()

    Returns whether the primary "external" storage device is removable. If true is returned, this device is for example an SD card that the user can remove. If false is returned, the storage is built into the device and can not be physically removed.

    See getExternalStorageDirectory() for more information.

  • isExternalStorageEmulated

    public static boolean isExternalStorageEmulated()

    Returns whether the device has an external storage device which is emulated. If true, the device does not have real external storage, and the directory returned by getExternalStorageDirectory() will be allocated using a portion of the internal storage system.

    Certain system services, such as the package manager, use this to determine where to install an application.

    Emulated external storage may also be encrypted - see DevicePolicyManager.setStorageEncryption( android.content.ComponentName, boolean) for additional details.