Directory (FoundationDB Java Client API)

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. In the present release, multiple directories may not be concurrently created within a single transaction. This restriction will be removed in a future release.

Method Summary

Methods
Modifier and Type	Method and Description
`Future<DirectorySubspace>`	`create(TransactionContext tcx, List<String> subpath)` Creates a subdirectory of this `Directory` located at `subpath` (creating parent directories if necessary).
`Future<DirectorySubspace>`	`create(TransactionContext tcx, List<String> subpath, byte[] layer)` Creates a subdirectory of this `Directory` located at `subpath` (creating parent directories if necessary).
`Future<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).
`Future<DirectorySubspace>`	`createOrOpen(TransactionContext tcx, List<String> subpath)` Creates or opens the subdirectory of this `Directory` located at `subpath` (creating parent directories, if necessary).
`Future<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).
`Future<Boolean>`	`exists(ReadTransactionContext tcx)` Checks if this `Directory` exists.
`Future<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`.
`Future<List<String>>`	`list(ReadTransactionContext tcx)` List the subdirectories of this directory.
`Future<List<String>>`	`list(ReadTransactionContext tcx, List<String> subpath)` List the subdirectories of this directory at a given `subpath`.
`Future<DirectorySubspace>`	`move(TransactionContext tcx, List<String> oldSubpath, List<String> newSubpath)` Moves the subdirectory of this `Directory` located at `oldSubpath` to `newSubpath`.
`Future<DirectorySubspace>`	`moveTo(TransactionContext tcx, List<String> newAbsolutePath)` Moves this `Directory` to the specified `newAbsolutePath`.
`Future<DirectorySubspace>`	`open(ReadTransactionContext tcx, List<String> subpath)` Opens the subdirectory of this `Directory` located at `subpath`.
`Future<DirectorySubspace>`	`open(ReadTransactionContext tcx, List<String> subpath, byte[] layer)` Opens the subdirectory of this `Directory` located at `subpath`.
`Future<Void>`	`remove(TransactionContext tcx)` Removes this `Directory` and all of its subdirectories, as well as all of their contents.
`Future<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.
`Future<Boolean>`	`removeIfExists(TransactionContext tcx)` Removes this `Directory` and all of its subdirectories, as well as all of their contents.
`Future<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 Detail
  - 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
```
Future<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 Future which will be set to the created or opened DirectorySubspace
  - createOrOpen
```
Future<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 Future 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 Future which will be set to the created or opened DirectorySubspace
  - open
```
Future<DirectorySubspace> open(ReadTransactionContext tcx,
                             List<String> subpath)
```
    Opens the subdirectory of this Directory located at subpath.
    The returned Future 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 Future which will be set to the opened DirectorySubspace
  - open
```
Future<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 Future 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 Future which will be set to the opened DirectorySubspace
  - create
```
Future<DirectorySubspace> create(TransactionContext tcx,
                               List<String> subpath)
```
    Creates a subdirectory of this Directory located at subpath (creating parent directories if necessary).
    The returned Future 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 Future which will be set to the created DirectorySubspace
  - create
```
Future<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 Future 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 Future which will be set to the created DirectorySubspace
  - create
```
Future<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 Future 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 Future which will be set to the created DirectorySubspace
  - moveTo
```
Future<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 Future 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 Future which will be set to the DirectorySubspace for this Directory at its new location.
  - move
```
Future<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 Future 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 Future which will be set to the DirectorySubspace for this Directory at its new location.
  - remove
```
Future<Void> remove(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.
    
    The returned Future can be set to the following errors:
    - NoSuchDirectoryException - if this Directory doesn't exist
    Parameters:
    tcx - the TransactionContext to execute this operation in
    
    Returns:
    a Future which will be set once this Directory has been removed
  - remove
```
Future<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 Future 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 Future which will be set once the Directory has been removed
  - removeIfExists
```
Future<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 Future which will be set to true once this Directory has been removed, or false if it didn't exist.
  - removeIfExists
```
Future<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 Future which will be set to true once the Directory has been removed, or false if it didn't exist.
  - list
```
Future<List<String>> list(ReadTransactionContext tcx)
```
    List the subdirectories of this directory.
    The returned Future 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 Future 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
```
Future<List<String>> list(ReadTransactionContext tcx,
                        List<String> subpath)
```
    List the subdirectories of this directory at a given subpath.
    The returned Future 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 Future 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
```
Future<Boolean> exists(ReadTransactionContext tcx)
```
    Checks if this Directory exists.
    
    Parameters:
    tcx - the ReadTransactionContext to execute this operation in
    
    Returns:
    a Future which will be set to true if this Directory exists, or false if it doesn't
  - exists
```
Future<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 Future which will be set to true if the specified subdirectory exists, or false if it doesn't

Interface Directory

Method Summary

Method Detail

getPath

getLayer

getDirectoryLayer

createOrOpen

createOrOpen

open

open

create

create

create

moveTo

move

remove

remove

removeIfExists

removeIfExists

list

list

exists

exists