com.github.fge.filesystem.provider

Class FileSystemProviderBase

java.lang.Object

java.nio.file.spi.FileSystemProvider

com.github.fge.filesystem.provider.FileSystemProviderBase

@ParametersAreNonnullByDefault
public abstract class FileSystemProviderBase
extends FileSystemProvider

Base FileSystemProvider implementation

Important note: in order to match the behaviour of the default filesystems, you should be aware of the following:

• The copy operation will not perform recursive copies; if the source is a non empty directory, the operation fails with DirectoryNotEmptyException. This class enforces this behaviour if the source and target paths are not on the same filesystem; if they are, this is then delegated to your own copy implementation.
• if the target path of a move operation exists and is a non empty directory, and you selected to replace the existing target path, the operation fails with DirectoryNotEmptyException; if the source and target paths are not on the same filesystem, this behaviour is enforced by this class; if they are on the same filesystem, this is delegated to your own move implementation.
• The deletion operation (delete(Path) and FileSystemProvider.deleteIfExists(Path) do not perform recursive deletions; if the target is a non empty directory, this method throws DirectoryNotEmptyException.

All methods of this class which accept options as arguments will check the validity of these options before performing the actual operation. Two exceptions are possible when checking options:

• UnsupportedOptionException,
• IllegalOptionSetException.

See Also:

FileSystemOptionsFactory, FileSystemDriver, FileSystemRepository.getDriver(Path)

Field Summary

Fields

Modifier and Type	Field and Description
protected FileSystemOptionsFactory	optionsFactory
protected FileSystemRepository	repository

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	FileSystemProviderBase(FileSystemRepository repository)

Method Summary

Methods

Modifier and Type	Method and Description
void	checkAccess(Path path, AccessMode... modes) Check whether a path exists and can be accessed using the given modes
void	copy(Path source, Path target, CopyOption... options) Copy a source path to a target path
void	createDirectory(Path dir, FileAttribute<?>... attrs) Create a directory
void	delete(Path path) Delete an entry on the filesystem
<V extends FileAttributeView> V	getFileAttributeView(Path path, Class<V> type, LinkOption... options)
FileStore	getFileStore(Path path)
FileSystem	getFileSystem(URI uri)
Path	getPath(URI uri)
String	getScheme()
boolean	isHidden(Path path) Tell whether the filesystem object pointed by the path (if any) is hidden
boolean	isSameFile(Path path, Path path2) Tell whether two paths represent exactly the same filesystem objects
void	move(Path source, Path target, CopyOption... options) Move a source path to a target path
SeekableByteChannel	newByteChannel(Path path, Set<? extends OpenOption> options, FileAttribute<?>... attrs) TODO: throws UnsupportedOperationException if attributes are specified
DirectoryStream<Path>	newDirectoryStream(Path dir, DirectoryStream.Filter<? super Path> filter) Open a new directory stream from a target path
FileSystem	newFileSystem(URI uri, Map<String,?> env)
InputStream	newInputStream(Path path, OpenOption... options) Open an input stream to an existing path
OutputStream	newOutputStream(Path path, OpenOption... options) Open an output stream to a given path
<A extends BasicFileAttributes> A	readAttributes(Path path, Class<A> type, LinkOption... options)
Map<String,Object>	readAttributes(Path path, String attributes, LinkOption... options)
void	setAttribute(Path path, String attribute, Object value, LinkOption... options)

Methods inherited from class java.nio.file.spi.FileSystemProvider

createLink, createSymbolicLink, deleteIfExists, installedProviders, newAsynchronousFileChannel, newFileChannel, newFileSystem, readSymbolicLink

Methods inherited from class java.lang.Object

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

Field Detail

repository

protected final FileSystemRepository repository

optionsFactory

protected final FileSystemOptionsFactory optionsFactory

Constructor Detail

FileSystemProviderBase

protected FileSystemProviderBase(FileSystemRepository repository)

Method Detail

getScheme

public final String getScheme()

Specified by:

getScheme in class FileSystemProvider

newFileSystem

public final FileSystem newFileSystem(URI uri,
                       Map<String,?> env)
                               throws IOException

Specified by:

newFileSystem in class FileSystemProvider

Throws:

IOException

getFileSystem

public final FileSystem getFileSystem(URI uri)

Specified by:

getFileSystem in class FileSystemProvider

getPath

public final Path getPath(URI uri)

Specified by:

getPath in class FileSystemProvider

newInputStream

public final InputStream newInputStream(Path path,
                         OpenOption... options)
                                 throws IOException

Open an input stream to an existing path

This method checks the existence of the file before delegating the creation of the input stream to the relevant driver. The driver is also responsible to deal with the target not being a directory.

Overrides:

newInputStream in class FileSystemProvider

Parameters:

path - the path to open

options - open options

Returns:

an input stream

Throws:

NoSuchFileException - file does not exist

IOException - other I/O exception

See Also:

FileSystemDriver.newInputStream(Path, Set)

newOutputStream

public final OutputStream newOutputStream(Path path,
                           OpenOption... options)
                                   throws IOException

Open an output stream to a given path

This class performs the following checks before delegating to the driver:

• if StandardOpenOption.CREATE_NEW is specified and the file already exists, throws FileAlreadyExistsException;
• if the file does not exist and StandardOpenOption.CREATE is not set, throws NoSuchFileException;
• if the file exists and cannot be written to, throws AccessDeniedException.

All other checks, such as for instance the target being a directory and not a file, are left to the driver.

Overrides:

newOutputStream in class FileSystemProvider

Parameters:

path - the path to open

options - the set of open options

Returns:

an output stream

Throws:

FileAlreadyExistsException - StandardOpenOption.CREATE_NEW was specified but the target already exists

AccessDeniedException - target exists but cannot be written to

IOException - other I/O exception

See Also:

FileSystemDriver.newOutputStream(Path, Set)

newByteChannel

public final SeekableByteChannel newByteChannel(Path path,
                                 Set<? extends OpenOption> options,
                                 FileAttribute<?>... attrs)
                                         throws IOException

TODO: throws UnsupportedOperationException if attributes are specified

Specified by:

newByteChannel in class FileSystemProvider

Parameters:

path - the path to open a channel to

options - the set of options

attrs - file attributes to set if file is created

Returns:

a new channel

Throws:

IOException - error creating the channel

See Also:

FileSystemDriver.newByteChannel(Path, Set, FileAttribute[])

newDirectoryStream

public final DirectoryStream<Path> newDirectoryStream(Path dir,
                                       DirectoryStream.Filter<? super Path> filter)
                                               throws IOException

Open a new directory stream from a target path

This method checks that the target path exists and that the process has read access to it before delegating the directory stream creation to the driver.

It is up to the driver to perform other checks (such as whether the target path is indeed a directory).

Specified by:

newDirectoryStream in class FileSystemProvider

Parameters:

dir - the path

filter - a filter for directory entries

Returns:

a directory stream

Throws:

NoSuchFileException - target path does not exist

IOException - other I/O exception

See Also:

FileSystemDriver.newDirectoryStream(Path, DirectoryStream.Filter)

createDirectory

public final void createDirectory(Path dir,
                   FileAttribute<?>... attrs)
                           throws IOException

Create a directory

TODO: UnsupportedOperationException if any attributes are specified

Specified by:

createDirectory in class FileSystemProvider

Parameters:

dir - the directory to create

attrs - attributes to the created directory

Throws:

IOException - directory creation failed

See Also:

FileSystemDriver.createDirectory(Path, FileAttribute[])

delete

public final void delete(Path path)
                  throws IOException

Delete an entry on the filesystem

This method will check whether the path actually exists before delegating to the driver.

Recall: this operation does not perform recursive deletions. It is up to the driver to check whether the target is a non empty directory, and fail with DirectoryNotEmptyException if this is the case.

Specified by:

delete in class FileSystemProvider

Parameters:

path - the path to delete

Throws:

NoSuchFileException - target does not exist

IOException - other I/O error

See Also:

FileSystemDriver.delete(Path)

copy

public final void copy(Path source,
        Path target,
        CopyOption... options)
                throws IOException

Copy a source path to a target path

This method will do the following before performing the actual copy:

• check that the source path exists;
• if StandardCopyOption.REPLACE_EXISTING is not set, check that the destination path does not exist.

Il will then delegate to the relevant driver if and only if both paths are issued from the same FileSystem. If not, it performs the copy itself.

Note that recursive copies are NOT performed by this method. Similarly, the driver SHOULD NOT perform recursive copies.

Specified by:

copy in class FileSystemProvider

Parameters:

source - the source path

target - the target path

options - the copy options

Throws:

NoSuchFileException - source path does not exist

FileAlreadyExistsException - destination path exists and StandardCopyOption.REPLACE_EXISTING was not set

IOException - other I/O error

See Also:

FileSystemDriver.copy(Path, Path, Set)

move

public final void move(Path source,
        Path target,
        CopyOption... options)
                throws IOException

Move a source path to a target path

This method will perform the following checks

• if the source does not exist, throws NoSuchFileException;
• if the target exists and StandardCopyOption.REPLACE_EXISTING is not set, throws FileAlreadyExistsException.

From this point on, it will delegate to the driver if and only if both the source and target are on the same filesystem. If this is not the case, TODO: implement metadata driver, for now it sucks

Specified by:

move in class FileSystemProvider

Parameters:

source - the path to move

target - the destination path

options - the set of copy options

Throws:

NoSuchFileException - the source does not exist

FileAlreadyExistsException - the target exists and StandardCopyOption.REPLACE_EXISTING was not set

IOException - other I/O exception

See Also:

FileSystemDriver.move(Path, Path, Set)

isSameFile

public final boolean isSameFile(Path path,
                 Path path2)
                         throws IOException

Tell whether two paths represent exactly the same filesystem objects

This method checks that both paths exist and have the same driver (which is the same as checking whether they are on the same filesystem, since no two filesystems share a driver), and then delegates to the driver to perform additional checks.

Specified by:

isSameFile in class FileSystemProvider

Parameters:

path - the first path

path2 - the second path

Returns:

true if and only if both paths point to the same filesystem object

Throws:

NoSuchFileException - one, or both, paths do not exist

IOException - error processing one, or both, paths

See Also:

FileSystemDriver.isSameFile(Path, Path)

isHidden

public final boolean isHidden(Path path)
                       throws IOException

Tell whether the filesystem object pointed by the path (if any) is hidden

Typically, on Unix systems, this will be for paths whose last name component (if any) starts with a dot.

Specified by:

isHidden in class FileSystemProvider

Parameters:

path - the path to check

Returns:

true if the file is considered hidden

Throws:

IOException - error accessing path information

See Also:

FileSystemDriver.isSameFile(Path, Path)

checkAccess

public final void checkAccess(Path path,
               AccessMode... modes)
                       throws IOException

Check whether a path exists and can be accessed using the given modes

Passing no modes argument typically only makes an existence check.

Specified by:

checkAccess in class FileSystemProvider

Parameters:

path - the path to check

modes - the modes to check against

Throws:

IOException - error accessing path information

See Also:

FileSystemDriver.checkAccess(Path, AccessMode...)

getFileAttributeView

public final <V extends FileAttributeView> V getFileAttributeView(Path path,
                                                   Class<V> type,
                                                   LinkOption... options)

Specified by:

getFileAttributeView in class FileSystemProvider

readAttributes

public final <A extends BasicFileAttributes> A readAttributes(Path path,
                                               Class<A> type,
                                               LinkOption... options)
                                                   throws IOException

Specified by:

readAttributes in class FileSystemProvider

Throws:

IOException

readAttributes

public final Map<String,Object> readAttributes(Path path,
                                String attributes,
                                LinkOption... options)
                                        throws IOException

Specified by:

readAttributes in class FileSystemProvider

Throws:

IOException

setAttribute

public final void setAttribute(Path path,
                String attribute,
                Object value,
                LinkOption... options)
                        throws IOException

Specified by:

setAttribute in class FileSystemProvider

Throws:

IOException

getFileStore

public final FileStore getFileStore(Path path)
                             throws IOException

Specified by:

getFileStore in class FileSystemProvider

Throws:

IOException