org.apache.hadoop.fs

Class TrashPolicy

java.lang.Object

org.apache.hadoop.conf.Configured

org.apache.hadoop.fs.TrashPolicy

All Implemented Interfaces:

Configurable

@InterfaceAudience.Public
 @InterfaceStability.Evolving
public abstract class TrashPolicy
extends Configured

This interface is used for implementing different Trash policies. Provides factory method to create instances of the configured Trash policy.

Field Summary

Fields

Modifier and Type	Field and Description
protected long	deletionInterval
protected FileSystem	fs
protected Path	trash

Constructor Summary

Constructors

Constructor and Description
TrashPolicy()

Method Summary

Modifier and Type	Method and Description
abstract void	createCheckpoint() Create a trash checkpoint.
abstract void	deleteCheckpoint() Delete old trash checkpoint(s).
abstract void	deleteCheckpointsImmediately() Delete all checkpoints immediately, ie empty trash.
abstract Path	getCurrentTrashDir() Get the current working directory of the Trash Policy This API does not work with files deleted from encryption zone when HDFS data encryption at rest feature is enabled as rename file between encryption zones or encryption zone and non-encryption zone is not allowed.
Path	getCurrentTrashDir(Path path) Get the current trash directory for path specified based on the Trash Policy
abstract Runnable	getEmptier() Return a Runnable that periodically empties the trash of all users, intended to be run by the superuser.
static TrashPolicy	getInstance(Configuration conf, FileSystem fs) Get an instance of the configured TrashPolicy based on the value of the configuration parameter fs.trash.classname.
static TrashPolicy	getInstance(Configuration conf, FileSystem fs, Path home) Deprecated. Use getInstance(Configuration, FileSystem) instead.
void	initialize(Configuration conf, FileSystem fs) Used to setup the trash policy.
abstract void	initialize(Configuration conf, FileSystem fs, Path home) Deprecated. Use initialize(Configuration, FileSystem) instead.
abstract boolean	isEnabled() Returns whether the Trash Policy is enabled for this filesystem.
abstract boolean	moveToTrash(Path path) Move a file or directory to the current trash directory.

Methods inherited from class org.apache.hadoop.conf.Configured

getConf, setConf

Methods inherited from class java.lang.Object

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

Field Detail

fs

protected FileSystem fs

trash

protected Path trash

deletionInterval

protected long deletionInterval

Constructor Detail

TrashPolicy

public TrashPolicy()

Method Detail

initialize

@Deprecated
public abstract void initialize(Configuration conf,
                                            FileSystem fs,
                                            Path home)

Deprecated. Use initialize(Configuration, FileSystem) instead.

Used to setup the trash policy. Must be implemented by all TrashPolicy implementations.

Parameters:

conf - the configuration to be used

fs - the filesystem to be used

home - the home directory

initialize

public void initialize(Configuration conf,
                       FileSystem fs)

Used to setup the trash policy. Must be implemented by all TrashPolicy implementations. Different from initialize(conf, fs, home), this one does not assume trash always under /user/$USER due to HDFS encryption zone.

Parameters:

conf - the configuration to be used

fs - the filesystem to be used

isEnabled

public abstract boolean isEnabled()

Returns whether the Trash Policy is enabled for this filesystem.

Returns:

if isEnabled true,not false.

moveToTrash

public abstract boolean moveToTrash(Path path)
                             throws IOException

Move a file or directory to the current trash directory.

Parameters:

path - the path.

Returns:

false if the item is already in the trash or trash is disabled

Throws:

IOException - raised on errors performing I/O.

createCheckpoint

public abstract void createCheckpoint()
                               throws IOException

Create a trash checkpoint.

Throws:

IOException - raised on errors performing I/O.

deleteCheckpoint

public abstract void deleteCheckpoint()
                               throws IOException

Delete old trash checkpoint(s).

Throws:

IOException - raised on errors performing I/O.

deleteCheckpointsImmediately

public abstract void deleteCheckpointsImmediately()
                                           throws IOException

Delete all checkpoints immediately, ie empty trash.

Throws:

IOException - raised on errors performing I/O.

getCurrentTrashDir

public abstract Path getCurrentTrashDir()

Get the current working directory of the Trash Policy This API does not work with files deleted from encryption zone when HDFS data encryption at rest feature is enabled as rename file between encryption zones or encryption zone and non-encryption zone is not allowed. The caller is recommend to use the new API TrashPolicy#getCurrentTrashDir(Path path). It returns the trash location correctly for the path specified no matter the path is in encryption zone or not.

Returns:

the path.

getCurrentTrashDir

public Path getCurrentTrashDir(Path path)
                        throws IOException

Get the current trash directory for path specified based on the Trash Policy

Parameters:

path - path to be deleted

Returns:

current trash directory for the path to be deleted

Throws:

IOException - raised on errors performing I/O.

getEmptier

public abstract Runnable getEmptier()
                             throws IOException

Return a Runnable that periodically empties the trash of all users, intended to be run by the superuser.

Returns:

Runnable.

Throws:

IOException - raised on errors performing I/O.

getInstance

@Deprecated
public static TrashPolicy getInstance(Configuration conf,
                                                  FileSystem fs,
                                                  Path home)

Deprecated. Use getInstance(Configuration, FileSystem) instead.

Get an instance of the configured TrashPolicy based on the value of the configuration parameter fs.trash.classname.

Parameters:

conf - the configuration to be used

fs - the file system to be used

home - the home directory

Returns:

an instance of TrashPolicy

getInstance

public static TrashPolicy getInstance(Configuration conf,
                                      FileSystem fs)

Get an instance of the configured TrashPolicy based on the value of the configuration parameter fs.trash.classname.

Parameters:

conf - the configuration to be used

fs - the file system to be used

Returns:

an instance of TrashPolicy