com.github.robtimus.filesystems.memory

Class MemoryFileSystemProvider

java.lang.Object

java.nio.file.spi.FileSystemProvider

com.github.robtimus.filesystems.memory.MemoryFileSystemProvider

public final class MemoryFileSystemProvider
extends FileSystemProvider

A provider for in-memory file systems.

Author:

Rob Spoor

Constructor Summary

Constructors

Constructor and Description
MemoryFileSystemProvider() Creates a new in-memory file system provider.

Method Summary

Modifier and Type	Method and Description
void	checkAccess(Path path, AccessMode... modes)
static void	clear() Clears all stored in-memory files and directories.
void	copy(Path source, Path target, CopyOption... options)
void	createDirectory(Path dir, FileAttribute<?>... attrs)
void	createLink(Path link, Path existing)
void	createSymbolicLink(Path link, Path target, FileAttribute<?>... attrs)
void	delete(Path path)
boolean	deleteIfExists(Path path)
static byte[]	getContent(Path path) Returns the content of an existing file.
static byte[]	getContent(String path) Returns the content of an existing file.
static String	getContentAsString(Path path) Returns the content of an existing file.
static String	getContentAsString(Path path, Charset charset) Returns the content of an existing file.
static String	getContentAsString(String path) Returns the content of an existing file.
static String	getContentAsString(String path, Charset charset) Returns the content of an existing file.
static Optional<String>	getContentAsStringIfExists(Path path) Returns the content of an existing file.
static Optional<String>	getContentAsStringIfExists(Path path, Charset charset) Returns the content of an existing file.
static Optional<String>	getContentAsStringIfExists(String path) Returns the content of an existing file.
static Optional<String>	getContentAsStringIfExists(String path, Charset charset) Returns the content of an existing file.
static Optional<byte[]>	getContentIfExists(Path path) Returns the content of a file.
static Optional<byte[]>	getContentIfExists(String path) Returns the content of an existing file.
<V extends FileAttributeView> V	getFileAttributeView(Path path, Class<V> type, LinkOption... options) Returns a file attribute view of a given type.
FileStore	getFileStore(Path path)
FileSystem	getFileSystem(URI uri) Returns the single in-memory file system.
Path	getPath(URI uri) Return a Path object by converting the given URI.
String	getScheme() Returns the URI scheme that identifies this provider: memory.
boolean	isHidden(Path path)
boolean	isSameFile(Path path, Path path2)
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)
FileChannel	newFileChannel(Path path, Set<? extends OpenOption> options, FileAttribute<?>... attrs)
FileSystem	newFileSystem(URI uri, Map<String,?> env) Constructs a new FileSystem object identified by a URI.
InputStream	newInputStream(Path path, OpenOption... options)
OutputStream	newOutputStream(Path path, OpenOption... options)
<A extends BasicFileAttributes> A	readAttributes(Path path, Class<A> type, LinkOption... options) Reads a file's attributes as a bulk operation.
Map<String,Object>	readAttributes(Path path, String attributes, LinkOption... options) Reads a set of file attributes as a bulk operation.
Path	readSymbolicLink(Path link)
void	setAttribute(Path path, String attribute, Object value, LinkOption... options) Sets the value of a file attribute.
static void	setContent(Path path, byte[] content) Sets the content of a file.
static void	setContent(String path, byte[] content) Sets the content of a file.
static void	setContentAsString(Path path, String content) Sets the content of a file.
static void	setContentAsString(Path path, String content, Charset charset) Sets the content of a file.
static void	setContentAsString(String path, String content) Sets the content of a file.
static void	setContentAsString(String path, String content, Charset charset) Sets the content of a file.

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

installedProviders, newAsynchronousFileChannel, newFileSystem

Methods inherited from class java.lang.Object

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

Constructor Detail

MemoryFileSystemProvider

public MemoryFileSystemProvider()

Creates a new in-memory file system provider.

Method Detail

getScheme

public String getScheme()

Returns the URI scheme that identifies this provider: memory.

Specified by:

getScheme in class FileSystemProvider

newFileSystem

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

Constructs a new FileSystem object identified by a URI.

Because there is only one single in-memory file system that is created automatically, this method will always throw a FileSystemAlreadyExistsException.

Specified by:

newFileSystem in class FileSystemProvider

Throws:

IOException

getFileSystem

public FileSystem getFileSystem(URI uri)

Returns the single in-memory file system.

The URI must have a scheme equal to getScheme().

Specified by:

getFileSystem in class FileSystemProvider

getPath

public Path getPath(URI uri)

Return a Path object by converting the given URI.

The URI must have a scheme equal to getScheme(). Its scheme specific part will be used as the path (either relative or absolute) for the returned Path object.

Specified by:

getPath in class FileSystemProvider

newInputStream

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

Overrides:

newInputStream in class FileSystemProvider

Throws:

IOException

newOutputStream

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

Overrides:

newOutputStream in class FileSystemProvider

Throws:

IOException

newFileChannel

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

Overrides:

newFileChannel in class FileSystemProvider

Throws:

IOException

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

createSymbolicLink

public void createSymbolicLink(Path link,
                               Path target,
                               FileAttribute<?>... attrs)
                        throws IOException

Overrides:

createSymbolicLink in class FileSystemProvider

Throws:

IOException

createLink

public void createLink(Path link,
                       Path existing)
                throws IOException

Overrides:

createLink in class FileSystemProvider

Throws:

IOException

delete

public void delete(Path path)
            throws IOException

Specified by:

delete in class FileSystemProvider

Throws:

IOException

deleteIfExists

public boolean deleteIfExists(Path path)
                       throws IOException

Overrides:

deleteIfExists in class FileSystemProvider

Throws:

IOException

readSymbolicLink

public Path readSymbolicLink(Path link)
                      throws IOException

Overrides:

readSymbolicLink 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)

Returns a file attribute view of a given type. This method works in exactly the manner specified by the Files.getFileAttributeView(Path, Class, LinkOption...) method.

This provider supports BasicFileAttributeView and MemoryFileAttributeView. All other classes will result in a null return value.

Specified by:

getFileAttributeView in class FileSystemProvider

readAttributes

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

Reads a file's attributes as a bulk operation. This method works in exactly the manner specified by the Files.readAttributes(Path, Class, LinkOption...) method.

This provider supports BasicFileAttributes and MemoryFileAttributes. All other classes will result in an UnsupportedOperationException to be thrown.

Specified by:

readAttributes in class FileSystemProvider

Throws:

IOException

readAttributes

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

Reads a set of file attributes as a bulk operation. This method works in exactly the manner specified by the Files.readAttributes(Path, String, LinkOption...) method.

This provider supports views basic and memory, where basic will be used if no view is given. All other views will result in an UnsupportedOperationException to be thrown.

Specified by:

readAttributes in class FileSystemProvider

Throws:

IOException

setAttribute

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

Sets the value of a file attribute. This method works in exactly the manner specified by the Files.setAttribute(Path, String, Object, LinkOption...) method.

This provider supports views basic and memory, where basic will be used if no view is given. All other views will result in an UnsupportedOperationException to be thrown.

Specified by:

setAttribute in class FileSystemProvider

Throws:

IOException

getContent

public static byte[] getContent(String path)
                         throws IOException

Returns the content of an existing file. This method is shorthand for the following:

 URI uri = URI.create("memory:" + path);
 return getContent(Paths.get(uri));

Parameters:

path - The path to the file to return the content of.

Returns:

The content of the given file.

Throws:

NullPointerException - If the given path is null.

IllegalArgumentException - If the path does not lead to a valid URI.

IOException - If an I/O error occurs.

Since:

1.1

See Also:

getContent(Path)

getContent

public static byte[] getContent(Path path)
                         throws IOException

Returns the content of an existing file.

This method works like Files.readAllBytes(Path) but is more optimized for in-memory paths.

Parameters:

path - The path to the file to return the content of.

Returns:

The content of the given file.

Throws:

NullPointerException - If the given path is null.

ProviderMismatchException - If the given path is not an in-memory path.

IOException - If an I/O error occurs.

Since:

1.1

getContentIfExists

public static Optional<byte[]> getContentIfExists(String path)
                                           throws IOException

Returns the content of an existing file. This method is shorthand for the following:

 URI uri = URI.create("memory:" + path);
 return getContentIfExists(Paths.get(uri));

Parameters:

path - The path to the file to return the content of.

Returns:

An Optional describing the content of the given file, or Optional.empty() if the file does not exist.

Throws:

NullPointerException - If the given path is null.

IllegalArgumentException - If the path does not lead to a valid URI.

IOException - If an I/O error occurs.

Since:

2.1

See Also:

getContent(Path)

getContentIfExists

public static Optional<byte[]> getContentIfExists(Path path)
                                           throws IOException

Returns the content of a file.

This method works like Files.readAllBytes(Path) but is more optimized for in-memory paths. It also does not fail if a file or any of its parent directories does not exist.

Parameters:

path - The path to the file to return the content of.

Returns:

An Optional describing the content of the given file, or Optional.empty() if the file does not exist.

Throws:

NullPointerException - If the given path is null.

ProviderMismatchException - If the given path is not an in-memory path.

IOException - If an I/O error occurs.

Since:

2.1

getContentAsString

public static String getContentAsString(String path)
                                 throws IOException

Returns the content of an existing file.

This method is wrapper around getContent(String) that converts the content into a string using the UTF-8 charset.

Parameters:

path - The path to the file to return the content of.

Returns:

The content of the given file.

Throws:

NullPointerException - If the given path is null.

IllegalArgumentException - If the path does not lead to a valid URI.

IOException - If an I/O error occurs.

Since:

2.1

getContentAsString

public static String getContentAsString(String path,
                                        Charset charset)
                                 throws IOException

Returns the content of an existing file.

This method is wrapper around getContent(String) that converts the content into a string.

Parameters:

path - The path to the file to return the content of.

charset - The charset to use for converting the contents into a string.

Returns:

The content of the given file.

Throws:

NullPointerException - If the given path or charset is null.

IllegalArgumentException - If the path does not lead to a valid URI.

IOException - If an I/O error occurs.

Since:

2.1

getContentAsString

public static String getContentAsString(Path path)
                                 throws IOException

Returns the content of an existing file.

This method is wrapper around getContent(Path) that converts the content into a string using the UTF-8 charset.

Parameters:

path - The path to the file to return the content of.

Returns:

The content of the given file.

Throws:

NullPointerException - If the given path is null.

ProviderMismatchException - If the given path is not an in-memory path.

IOException - If an I/O error occurs.

Since:

2.1

getContentAsString

public static String getContentAsString(Path path,
                                        Charset charset)
                                 throws IOException

Returns the content of an existing file.

This method is wrapper around getContent(Path) that converts the content into a string.

Parameters:

path - The path to the file to return the content of.

charset - The charset to use for converting the contents into a string.

Returns:

The content of the given file.

Throws:

NullPointerException - If the given path or charset is null.

ProviderMismatchException - If the given path is not an in-memory path.

IOException - If an I/O error occurs.

Since:

2.1

getContentAsStringIfExists

public static Optional<String> getContentAsStringIfExists(String path)
                                                   throws IOException

Returns the content of an existing file.

This method is wrapper around getContentIfExists(String) that converts the content into a string using the UTF-8 charset.

Parameters:

path - The path to the file to return the content of.

Returns:

An Optional describing the content of the given file, or Optional.empty() if the file does not exist.

Throws:

NullPointerException - If the given path is null.

IllegalArgumentException - If the path does not lead to a valid URI.

IOException - If an I/O error occurs.

Since:

2.1

getContentAsStringIfExists

public static Optional<String> getContentAsStringIfExists(String path,
                                                          Charset charset)
                                                   throws IOException

Returns the content of an existing file.

This method is wrapper around getContentIfExists(String) that converts the content into a string.

Parameters:

path - The path to the file to return the content of.

charset - The charset to use for converting the contents into a string.

Returns:

An Optional describing the content of the given file, or Optional.empty() if the file does not exist.

Throws:

NullPointerException - If the given path or charset is null.

IllegalArgumentException - If the path does not lead to a valid URI.

IOException - If an I/O error occurs.

Since:

2.1

getContentAsStringIfExists

public static Optional<String> getContentAsStringIfExists(Path path)
                                                   throws IOException

Returns the content of an existing file.

This method is wrapper around getContentIfExists(Path) that converts the content into a string using the UTF-8 charset.

Parameters:

path - The path to the file to return the content of.

Returns:

An Optional describing the content of the given file, or Optional.empty() if the file does not exist.

Throws:

NullPointerException - If the given path is null.

ProviderMismatchException - If the given path is not an in-memory path.

IOException - If an I/O error occurs.

Since:

2.1

getContentAsStringIfExists

public static Optional<String> getContentAsStringIfExists(Path path,
                                                          Charset charset)
                                                   throws IOException

Returns the content of an existing file.

This method is wrapper around getContentIfExists(Path) that converts the content into a string.

Parameters:

path - The path to the file to return the content of.

charset - The charset to use for converting the contents into a string.

Returns:

An Optional describing the content of the given file, or Optional.empty() if the file does not exist.

Throws:

NullPointerException - If the given path or charset is null.

ProviderMismatchException - If the given path is not an in-memory path.

IOException - If an I/O error occurs.

Since:

2.1

setContent

public static void setContent(String path,
                              byte[] content)
                       throws IOException

Sets the content of a file. If the file does not exist it will be created. This method is shorthand for the following:

 URI uri = URI.create("memory:" + path);
 setContents(Paths.get(uri), content);

Parameters:

path - The path to the file to set the content of.

content - The new content for the file.

Throws:

NullPointerException - If the given path or content is null.

IllegalArgumentException - If the path does not lead to a valid URI.

IOException - If an I/O error occurs.

Since:

1.1

See Also:

setContent(Path, byte[])

setContent

public static void setContent(Path path,
                              byte[] content)
                       throws IOException

Sets the content of a file. If the file does not exist it will be created.

This method works like Files.write(Path, byte[], OpenOption...) with no options given but is more optimized for in-memory paths. It does perform the necessary access checks on the file and/or its parent directory.

Parameters:

path - The path to the file to set the content of.

content - The new content for the file.

Throws:

NullPointerException - If the given path or content is null.

ProviderMismatchException - If the given path is not an in-memory path.

IOException - If an I/O error occurs.

Since:

1.1

setContentAsString

public static void setContentAsString(String path,
                                      String content)
                               throws IOException

Sets the content of a file. If the file does not exist it will be created.

This method is wrapper around setContent(String, byte[]) that converts the content into bytes using the UTF-8 charset.

Parameters:

path - The path to the file to set the content of.

content - The new content for the file.

Throws:

NullPointerException - If the given path, content or charset is null.

IllegalArgumentException - If the path does not lead to a valid URI.

IOException - If an I/O error occurs.

Since:

2.1

setContentAsString

public static void setContentAsString(String path,
                                      String content,
                                      Charset charset)
                               throws IOException

Sets the content of a file. If the file does not exist it will be created.

This method is wrapper around setContent(String, byte[]) that converts the content into bytes.

Parameters:

path - The path to the file to set the content of.

content - The new content for the file.

charset - The charset to use for converting the contents into bytes.

Throws:

NullPointerException - If the given path, content or charset is null.

IllegalArgumentException - If the path does not lead to a valid URI.

IOException - If an I/O error occurs.

Since:

2.1

setContentAsString

public static void setContentAsString(Path path,
                                      String content)
                               throws IOException

Sets the content of a file. If the file does not exist it will be created.

This method is wrapper around setContent(Path, byte[]) that converts the content into bytes using the UTF-8 charset.

Parameters:

path - The path to the file to set the content of.

content - The new content for the file.

Throws:

NullPointerException - If the given path, content or charset is null.

ProviderMismatchException - If the given path is not an in-memory path.

IOException - If an I/O error occurs.

Since:

2.1

setContentAsString

public static void setContentAsString(Path path,
                                      String content,
                                      Charset charset)
                               throws IOException

Sets the content of a file. If the file does not exist it will be created.

This method is wrapper around setContent(Path, byte[]) that converts the content into bytes.

Parameters:

path - The path to the file to set the content of.

content - The new content for the file.

charset - The charset to use for converting the contents into bytes.

Throws:

NullPointerException - If the given path, content or charset is null.

ProviderMismatchException - If the given path is not an in-memory path.

IOException - If an I/O error occurs.

Since:

2.1

clear

public static void clear()

Clears all stored in-memory files and directories. Afterwards only the root directory will exist, and its read-only and hidden attributes will have both been reset to false.

Since:

1.1