Package io.roastedroot.zerofs

Class SystemZeroFsFileSystemProvider

java.lang.Object

java.nio.file.spi.FileSystemProvider

io.roastedroot.zerofs.SystemZeroFsFileSystemProvider

public final class SystemZeroFsFileSystemProvider
extends FileSystemProvider

FileSystemProvider implementation for ZeroFs that is loaded by the system as a service. This implementation only serves as a cache for file system instances and does not implement actual file system operations.

While this class is public, it should not be used directly. To create a new file system instance, see ZeroFs. For other operations, use the public APIs in java.nio.file.

Since:

1.1

Field Summary

Fields

Modifier and Type	Field	Description
(package private) static final String	FILE_SYSTEM_KEY	Env map key that maps to the already-created FileSystem instance in newFileSystem.
private static final WeakValueConcurrentMap<URI,FileSystem>	fileSystems	Cache of file systems that have been created but not closed.

Constructor Summary

Constructors

Constructor	Description
SystemZeroFsFileSystemProvider()	Deprecated. Not intended to be called directly; this class is only for use by Java itself.

Method Summary

Modifier and Type	Method	Description
void	checkAccess(Path path, AccessMode... modes)
void	copy(Path source, Path target, CopyOption... options)
void	createDirectory(Path dir, FileAttribute<?>... attrs)
void	delete(Path path)
<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)
boolean	isSameFile(Path path, Path path2)
private static boolean	isValidFileSystemUri(URI uri)	Returns whether or not the given URI is valid as a base file system URI.
void	move(Path source, Path target, CopyOption... options)
SeekableByteChannel	newByteChannel(Path path, Set<? extends OpenOption> options, FileAttribute<?>... attrs)
DirectoryStream<Path>	newDirectoryStream(Path dir, DirectoryStream.Filter<? super Path> filter)
FileSystem	newFileSystem(URI uri, Map<String,?> env)
FileSystem	newFileSystem(Path path, Map<String,?> env)
<A extends BasicFileAttributes> A	readAttributes(Path path, Class<A> type, LinkOption... options)
Map<String,Object>	readAttributes(Path path, String attributes, LinkOption... options)
static Runnable	removeFileSystemRunnable(URI uri)	Returns a runnable that, when run, removes the file system with the given URI from this provider.
void	setAttribute(Path path, String attribute, Object value, LinkOption... options)
(package private) static boolean	stringIsNullOrEmpty(String string)
private static URI	toFileSystemUri(URI uri)	Returns the given URI with any path, query or fragment stripped off.
private static Path	toPath(FileSystem fileSystem, URI uri)	Invokes the toPath(URI) method on the given FileSystem.

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

createLink, createSymbolicLink, deleteIfExists, installedProviders, newAsynchronousFileChannel, newFileChannel, newInputStream, newOutputStream, readSymbolicLink

Methods inherited from class java.lang.Object

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

Field Details

FILE_SYSTEM_KEY

static final String FILE_SYSTEM_KEY

Env map key that maps to the already-created FileSystem instance in newFileSystem.

See Also:

• Constant Field Values

fileSystems

private static final WeakValueConcurrentMap<URI,FileSystem> fileSystems

Cache of file systems that have been created but not closed.

This cache is static to ensure that even when this provider isn't loaded by the system class loader, meaning that a new instance of it must be created each time one of the methods on FileSystems or Paths.get(URI) is called, cached file system instances are still available.

The cache uses weak values so that it doesn't prevent file systems that are created but not closed from being garbage collected if no references to them are held elsewhere. This is a compromise between ensuring that any file URI continues to work as long as the file system hasn't been closed (which is technically the correct thing to do but unlikely to be something that most users care about) and ensuring that users don't get unexpected leaks of large amounts of memory because they're creating many file systems in tests but forgetting to close them (which seems likely to happen sometimes). Users that want to ensure that a file system won't be garbage collected just need to ensure they hold a reference to it somewhere for as long as they need it to stick around.

Constructor Details

SystemZeroFsFileSystemProvider

@Deprecated
public SystemZeroFsFileSystemProvider()

Deprecated.

Not intended to be called directly; this class is only for use by Java itself.

Method Details

getScheme

public String getScheme()

Specified by:

getScheme in class FileSystemProvider

newFileSystem

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

Specified by:

newFileSystem in class FileSystemProvider

Throws:

IOException

getFileSystem

public FileSystem getFileSystem(URI uri)

Specified by:

getFileSystem in class FileSystemProvider

getPath

public Path getPath(URI uri)

Specified by:

getPath in class FileSystemProvider

stringIsNullOrEmpty

static boolean stringIsNullOrEmpty(String string)

isValidFileSystemUri

private static boolean isValidFileSystemUri(URI uri)

Returns whether or not the given URI is valid as a base file system URI. It must not have a path, query or fragment.

toFileSystemUri

private static URI toFileSystemUri(URI uri)

Returns the given URI with any path, query or fragment stripped off.

toPath

private static Path toPath(FileSystem fileSystem,
 URI uri)

Invokes the toPath(URI) method on the given FileSystem.

newFileSystem

public FileSystem newFileSystem(Path path,
 Map<String,?> env)
                         throws IOException

Overrides:

newFileSystem in class FileSystemProvider

Throws:

IOException

removeFileSystemRunnable

public static Runnable removeFileSystemRunnable(URI uri)

Returns a runnable that, when run, removes the file system with the given URI from this provider.

newByteChannel

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

Specified by:

newByteChannel in class FileSystemProvider

Throws:

IOException

newDirectoryStream

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

Specified by:

newDirectoryStream in class FileSystemProvider

Throws:

IOException

createDirectory

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

Specified by:

createDirectory in class FileSystemProvider

Throws:

IOException

delete

public void delete(Path path)
            throws IOException

Specified by:

delete in class FileSystemProvider

Throws:

IOException

copy

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

Specified by:

copy in class FileSystemProvider

Throws:

IOException

move

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

Specified by:

move in class FileSystemProvider

Throws:

IOException

isSameFile

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

Specified by:

isSameFile in class FileSystemProvider

Throws:

IOException

isHidden

public boolean isHidden(Path path)
                 throws IOException

Specified by:

isHidden in class FileSystemProvider

Throws:

IOException

getFileStore

public FileStore getFileStore(Path path)
                       throws IOException

Specified by:

getFileStore in class FileSystemProvider

Throws:

IOException

checkAccess

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

Specified by:

checkAccess in class FileSystemProvider

Throws:

IOException

getFileAttributeView

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

Specified by:

getFileAttributeView in class FileSystemProvider

readAttributes

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

Specified by:

readAttributes in class FileSystemProvider

Throws:

IOException

readAttributes

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

Specified by:

readAttributes in class FileSystemProvider

Throws:

IOException

setAttribute

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

Specified by:

setAttribute in class FileSystemProvider

Throws:

IOException