Package com.apple.foundationdb.directory

Interface Directory

All Known Implementing Classes:

DirectoryLayer, DirectorySubspace

public interface Directory

Represents a directory in the DirectoryLayer. A Directory stores the path at which it is located and the layer that was used to create it. The Directory interface contains methods to operate on itself and its subdirectories.

Method Summary

Modifier and Type	Method	Description
default CompletableFuture<DirectorySubspace>	create(TransactionContext tcx, List<String> subpath)	Creates a subdirectory of this Directory located at subpath (creating parent directories if necessary).
default CompletableFuture<DirectorySubspace>	create(TransactionContext tcx, List<String> subpath, byte[] layer)	Creates a subdirectory of this Directory located at subpath (creating parent directories if necessary).
CompletableFuture<DirectorySubspace>	create(TransactionContext tcx, List<String> subpath, byte[] layer, byte[] prefix)	Creates a subdirectory of this Directory located at subpath (creating parent directories if necessary).
default CompletableFuture<DirectorySubspace>	createOrOpen(TransactionContext tcx, List<String> subpath)	Creates or opens the subdirectory of this Directory located at subpath (creating parent directories, if necessary).
CompletableFuture<DirectorySubspace>	createOrOpen(TransactionContext tcx, List<String> subpath, byte[] layer)	Creates or opens the subdirectory of this Directory located at subpath (creating parent directories, if necessary).
default CompletableFuture<Boolean>	exists(ReadTransactionContext tcx)	Checks if this Directory exists.
CompletableFuture<Boolean>	exists(ReadTransactionContext tcx, List<String> subpath)	Checks if the subdirectory of this Directory located at subpath exists.
DirectoryLayer	getDirectoryLayer()	Get the DirectoryLayer that was used to create this Directory.
byte[]	getLayer()	Gets the layer byte string that was stored when this Directory was created.
List<String>	getPath()	Gets the path represented by this Directory.
default CompletableFuture<List<String>>	list(ReadTransactionContext tcx)	List the subdirectories of this directory.
CompletableFuture<List<String>>	list(ReadTransactionContext tcx, List<String> subpath)	List the subdirectories of this directory at a given subpath.
CompletableFuture<DirectorySubspace>	move(TransactionContext tcx, List<String> oldSubpath, List<String> newSubpath)	Moves the subdirectory of this Directory located at oldSubpath to newSubpath.
CompletableFuture<DirectorySubspace>	moveTo(TransactionContext tcx, List<String> newAbsolutePath)	Moves this Directory to the specified newAbsolutePath.
default CompletableFuture<DirectorySubspace>	open(ReadTransactionContext tcx, List<String> subpath)	Opens the subdirectory of this Directory located at subpath.
CompletableFuture<DirectorySubspace>	open(ReadTransactionContext tcx, List<String> subpath, byte[] layer)	Opens the subdirectory of this Directory located at subpath.
default CompletableFuture<Void>	remove(TransactionContext tcx)	Removes this Directory and all of its subdirectories, as well as all of their contents.
CompletableFuture<Void>	remove(TransactionContext tcx, List<String> subpath)	Removes the subdirectory of this Directory located at subpath and all of its subdirectories, as well as all of their contents.
default CompletableFuture<Boolean>	removeIfExists(TransactionContext tcx)	Removes this Directory and all of its subdirectories, as well as all of their contents.
CompletableFuture<Boolean>	removeIfExists(TransactionContext tcx, List<String> subpath)	Removes the subdirectory of this Directory located at subpath and all of its subdirectories, as well as all of their contents.

Method Details

getPath

List<String> getPath()

Gets the path represented by this Directory.

Returns:

this Directory's path

getLayer

byte[] getLayer()

Gets the layer byte string that was stored when this Directory was created.

Returns:

this Directory's layer byte string

getDirectoryLayer

DirectoryLayer getDirectoryLayer()

Get the DirectoryLayer that was used to create this Directory.

Returns:

the DirectoryLayer that created this Directory

createOrOpen

default CompletableFuture<DirectorySubspace> createOrOpen(TransactionContext tcx,
 List<String> subpath)

Creates or opens the subdirectory of this Directory located at subpath (creating parent directories, if necessary).

Parameters:

tcx - the TransactionContext to execute this operation in

subpath - a List<String> specifying a subpath of this Directory

Returns:

a CompletableFuture which will be set to the created or opened DirectorySubspace

createOrOpen

CompletableFuture<DirectorySubspace> createOrOpen(TransactionContext tcx,
 List<String> subpath,
 byte[] layer)

Creates or opens the subdirectory of this Directory located at subpath (creating parent directories, if necessary). If the directory is new, then the layer byte string will be recorded as its layer. If the directory already exists, the layer byte string will be compared against the layer set when the directory was created.

The returned CompletableFuture can be set to the following errors:

• MismatchedLayerException - if the directory has already been created with a different layer byte string

Parameters:

tcx - the TransactionContext to execute this operation in

subpath - a List<String> specifying a subpath of this Directory

layer - a byte[] specifying a layer to set on a new directory or check for on an existing directory

Returns:

a CompletableFuture which will be set to the created or opened DirectorySubspace

open

default CompletableFuture<DirectorySubspace> open(ReadTransactionContext tcx,
 List<String> subpath)

Opens the subdirectory of this Directory located at subpath.

The returned CompletableFuture can be set to the following errors:

• NoSuchDirectoryException - if the directory does not exist

Parameters:

tcx - the ReadTransactionContext to execute this operation in

subpath - a List<String> specifying a subpath of this Directory

Returns:

a CompletableFuture which will be set to the opened DirectorySubspace

open

CompletableFuture<DirectorySubspace> open(ReadTransactionContext tcx,
 List<String> subpath,
 byte[] layer)

Opens the subdirectory of this Directory located at subpath. The layer byte string will be compared against the layer set when the directory was created.

The returned CompletableFuture can be set to the following errors:

• MismatchedLayerException - if the directory was created with a different layer byte string
• NoSuchDirectoryException - if the directory does not exist

Parameters:

tcx - the ReadTransactionContext to execute this operation in

subpath - a List<String> specifying a subpath of this Directory

layer - a byte[] specifying the expected layer

Returns:

a CompletableFuture which will be set to the opened DirectorySubspace

create

default CompletableFuture<DirectorySubspace> create(TransactionContext tcx,
 List<String> subpath)

Creates a subdirectory of this Directory located at subpath (creating parent directories if necessary).

The returned CompletableFuture can be set to the following errors:

• DirectoryAlreadyExistsException - if the given directory already exists

Parameters:

tcx - the TransactionContext to execute this operation in

subpath - a List<String> specifying a subpath of this Directory

Returns:

a CompletableFuture which will be set to the created DirectorySubspace

create

default CompletableFuture<DirectorySubspace> create(TransactionContext tcx,
 List<String> subpath,
 byte[] layer)

Creates a subdirectory of this Directory located at subpath (creating parent directories if necessary). The layer byte string will be recorded as the new directory's layer and checked by future calls to open(ReadTransactionContext, List, byte[]).

The returned CompletableFuture can be set to the following errors:

• DirectoryAlreadyExistsException - if the given directory already exists

Parameters:

tcx - the TransactionContext to execute this operation in

subpath - a List<String> specifying a subpath of this Directory

layer - a byte[] specifying a layer to set for the directory

Returns:

a CompletableFuture which will be set to the created DirectorySubspace

create

CompletableFuture<DirectorySubspace> create(TransactionContext tcx,
 List<String> subpath,
 byte[] layer,
 byte[] prefix)

Creates a subdirectory of this Directory located at subpath (creating parent directories if necessary). The layer byte string will be recorded as the new directory's layer and checked by future calls to open(ReadTransactionContext, List, byte[]). The specified prefix will be used for this directory's contents instead of allocating a prefix automatically.

The returned CompletableFuture can be set to the following errors:

• DirectoryAlreadyExistsException - if the given directory already exists

Parameters:

tcx - the TransactionContext to execute this operation in

subpath - a List<String> specifying a subpath of this Directory

layer - a byte[] specifying a layer to set for the directory

prefix - a byte[] specifying the key prefix to use for the directory's contents

Returns:

a CompletableFuture which will be set to the created DirectorySubspace

moveTo

CompletableFuture<DirectorySubspace> moveTo(TransactionContext tcx,
 List<String> newAbsolutePath)

Moves this Directory to the specified newAbsolutePath.

There is no effect on the physical prefix of the given directory, or on clients that already have the directory open.

It is invalid to move a directory to:

• A location where a directory already exists
• A location whose parent does not exist
• A subdirectory of itself
• A different partition

The returned CompletableFuture can be set to the following errors:

• NoSuchDirectoryException - if this Directory doesn't exist
• DirectoryAlreadyExistsException - if a directory already exists at newAbsolutePath
• DirectoryMoveException - if an invalid move location is specified

Parameters:

tcx - the TransactionContext to execute this operation in

newAbsolutePath - a List<String> specifying the new absolute path for this Directory

Returns:

a CompletableFuture which will be set to the DirectorySubspace for this Directory at its new location.

move

CompletableFuture<DirectorySubspace> move(TransactionContext tcx,
 List<String> oldSubpath,
 List<String> newSubpath)

Moves the subdirectory of this Directory located at oldSubpath to newSubpath.

There is no effect on the physical prefix of the given directory, or on clients that already have the directory open.

It is invalid to move a directory to:

• A location where a directory already exists
• A location whose parent does not exist
• A subdirectory of itself
• A different partition

The returned CompletableFuture can be set to the following errors:

• NoSuchDirectoryException - if no Directory exists at oldSubpath
• DirectoryAlreadyExistsException - if a directory already exists at newSubpath
• DirectoryMoveException - if an invalid move location is specified

Parameters:

tcx - the TransactionContext to execute this operation in

oldSubpath - a List<String> specifying the subpath of the directory to move

newSubpath - a List<String> specifying the subpath to move to

Returns:

a CompletableFuture which will be set to the DirectorySubspace for this Directory at its new location.

remove

default CompletableFuture<Void> remove(TransactionContext tcx)

Removes this Directory and all of its subdirectories, as well as all of their contents. This should not be called on the root directory, or it will result in the returned future being set to a DirectoryException.

Warning: Clients that have already opened the directory might still insert data into its contents after it is removed.

The returned CompletableFuture can be set to the following errors:

• NoSuchDirectoryException - if this Directory doesn't exist
• DirectoryException - if this is called on the root directory

Parameters:

tcx - the TransactionContext to execute this operation in

Returns:

a CompletableFuture which will be set once this Directory has been removed

remove

CompletableFuture<Void> remove(TransactionContext tcx,
 List<String> subpath)

Removes the subdirectory of this Directory located at subpath and all of its subdirectories, as well as all of their contents.

Warning: Clients that have already opened the directory might still insert data into its contents after it is removed.

The returned CompletableFuture can be set to the following errors:

• NoSuchDirectoryException - if no directory exists at subpath

Parameters:

tcx - the TransactionContext to execute this operation in

subpath - a List<String> specifying a subpath of this Directory

Returns:

a CompletableFuture which will be set once the Directory has been removed

removeIfExists

default CompletableFuture<Boolean> removeIfExists(TransactionContext tcx)

Removes this Directory and all of its subdirectories, as well as all of their contents.

Warning: Clients that have already opened the directory might still insert data into its contents after it is removed.

Parameters:

tcx - the TransactionContext to execute this operation in

Returns:

a CompletableFuture which will be set to true once this Directory has been removed, or false if it didn't exist.

removeIfExists

CompletableFuture<Boolean> removeIfExists(TransactionContext tcx,
 List<String> subpath)

Removes the subdirectory of this Directory located at subpath and all of its subdirectories, as well as all of their contents.

Warning: Clients that have already opened the directory might still insert data into its contents after it is removed.

Parameters:

tcx - the TransactionContext to execute this operation in

subpath - a List<String> specifying a subpath of this Directory

Returns:

a CompletableFuture which will be set to true once the Directory has been removed, or false if it didn't exist.

list

default CompletableFuture<List<String>> list(ReadTransactionContext tcx)

List the subdirectories of this directory.

The returned CompletableFuture can be set to the following errors:

• NoSuchDirectoryException - if this Directory doesn't exists

Parameters:

tcx - the ReadTransactionContext to execute this operation in

Returns:

a CompletableFuture which will be set to a List<String> of names of the subdirectories of this Directory. Each name is a unicode string representing the last component of a subdirectory's path.

list

CompletableFuture<List<String>> list(ReadTransactionContext tcx,
 List<String> subpath)

List the subdirectories of this directory at a given subpath.

The returned CompletableFuture can be set to the following errors:

• NoSuchDirectoryException - if no directory exists at subpath

Parameters:

tcx - the ReadTransactionContext to execute this operation in

subpath - a List<String> specifying a subpath of this Directory

Returns:

a CompletableFuture which will be set to a List<String> of names of the subdirectories of the directory at subpath. Each name is a unicode string representing the last component of a subdirectory's path.

exists

default CompletableFuture<Boolean> exists(ReadTransactionContext tcx)

Checks if this Directory exists.

Parameters:

tcx - the ReadTransactionContext to execute this operation in

Returns:

a CompletableFuture which will be set to true if this Directory exists, or false if it doesn't

exists

CompletableFuture<Boolean> exists(ReadTransactionContext tcx,
 List<String> subpath)

Checks if the subdirectory of this Directory located at subpath exists.

Parameters:

tcx - the TransactionContext to execute this operation in

subpath - a List<String> specifying a subpath of this Directory

Returns:

a CompletableFuture which will be set to true if the specified subdirectory exists, or false if it doesn't