org.jboss.vfs.spi

Interface FileSystem

All Superinterfaces:

AutoCloseable, Closeable

All Known Implementing Classes:

AssemblyFileSystem, JavaZipFileSystem, RealFileSystem, RootFileSystem

public interface FileSystem
extends Closeable

A file system which is mounted in to the VFS. This is the driver class for a given virtual file system type. An instance of FileSystem will be mounted at some point on a VFS. The specific instance is only called when a file from this filesystem is called upon. The path components passed in to the operations are canonical, with no "." or ".." components.

Author:

David M. Lloyd

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Destroy this filesystem instance.
boolean	delete(VirtualFile mountPoint, VirtualFile target) Attempt to delete a virtual file within this filesystem.
boolean	exists(VirtualFile mountPoint, VirtualFile target) Ascertain the existance of a virtual file within this filesystem.
CodeSigner[]	getCodeSigners(VirtualFile mountPoint, VirtualFile target) Get the CodeSigners for a the virtual file.
List<String>	getDirectoryEntries(VirtualFile mountPoint, VirtualFile target) Read a directory.
File	getFile(VirtualFile mountPoint, VirtualFile target) Get a real File for the given path within this filesystem.
long	getLastModified(VirtualFile mountPoint, VirtualFile target) Get the last modification time of a virtual file within this filesystem.
File	getMountSource() Get the File source provided at mount time.
URI	getRootURI() Get the root URI for this file system, or null if there is no valid root URI.
long	getSize(VirtualFile mountPoint, VirtualFile target) Get the size of a virtual file within this filesystem.
boolean	isDirectory(VirtualFile mountPoint, VirtualFile target) Ascertain whether a virtual file within this filesystem is a directory.
boolean	isFile(VirtualFile mountPoint, VirtualFile target) Ascertain whether a virtual file within this filesystem is a plain file.
boolean	isReadOnly() Determine whether this filesystem is read-only.
InputStream	openInputStream(VirtualFile mountPoint, VirtualFile target) Open an input stream for the file at the given relative path.

Method Detail

getFile

File getFile(VirtualFile mountPoint,
           VirtualFile target)
             throws IOException

Get a real File for the given path within this filesystem. Some filesystem types will need to make a copy in order to return this file; such copies should be cached and retained until the filesystem is closed. Depending on the file type, the real path of the returned File may or may not bear a relationship to the virtual path provided; if such a relationship is required, it must be negotiated at the time the filesystem is mounted.

Parameters:

mountPoint - the mount point of the filesystem instance (guaranteed to be a parent of target)

target - the virtual file to act upon

Returns:

the file instance

Throws:

IOException - if an I/O error occurs

openInputStream

InputStream openInputStream(VirtualFile mountPoint,
                          VirtualFile target)
                            throws IOException

Open an input stream for the file at the given relative path.

Parameters:

mountPoint - the mount point of the filesystem instance (guaranteed to be a parent of target)

target - the virtual file to act upon

Returns:

the input stream

Throws:

IOException - if an I/O error occurs

isReadOnly

boolean isReadOnly()

Determine whether this filesystem is read-only. A read-only filesystem prohibits file modification or deletion. It is not an error to mount a read-write filesystem within a read-only filesystem however (this operation does not take place within the FileSystem implementation).

Returns:

true if the filesystem is read-only

delete

boolean delete(VirtualFile mountPoint,
             VirtualFile target)

Attempt to delete a virtual file within this filesystem.

Parameters:

mountPoint - the mount point of the filesystem instance (guaranteed to be a parent of target)

target - the virtual file to act upon

Returns:

true if the file was deleted, false if it failed for any reason

getSize

long getSize(VirtualFile mountPoint,
           VirtualFile target)

Get the size of a virtual file within this filesystem.

Parameters:

mountPoint - the mount point of the filesystem instance (guaranteed to be a parent of target)

target - the virtual file to act upon

Returns:

the size, in bytes, or 0L if the file does not exist or is a directory

getLastModified

long getLastModified(VirtualFile mountPoint,
                   VirtualFile target)

Get the last modification time of a virtual file within this filesystem.

Parameters:

mountPoint - the mount point of the filesystem instance (guaranteed to be a parent of target)

target - the virtual file to act upon

Returns:

the modification time in milliseconds, or 0L if the file does not exist or if an error occurs

exists

boolean exists(VirtualFile mountPoint,
             VirtualFile target)

Ascertain the existance of a virtual file within this filesystem.

Parameters:

mountPoint - the mount point of the filesystem instance (guaranteed to be a parent of target)

target - the virtual file to act upon

Returns:

true if the file exists, false otherwise

Throws:

IOException - if an I/O error occurs

isFile

boolean isFile(VirtualFile mountPoint,
             VirtualFile target)

Ascertain whether a virtual file within this filesystem is a plain file.

Parameters:

mountPoint - the mount point of the filesystem instance (guaranteed to be a parent of target)

target - the virtual file to act upon

Returns:

true if the file exists and is a plain file, false otherwise

isDirectory

boolean isDirectory(VirtualFile mountPoint,
                  VirtualFile target)

Ascertain whether a virtual file within this filesystem is a directory.

Parameters:

mountPoint - the mount point of the filesystem instance (guaranteed to be a parent of target)

target - the virtual file to act upon

Returns:

true if the file exists and is a directory, false otherwise

getDirectoryEntries

List<String> getDirectoryEntries(VirtualFile mountPoint,
                               VirtualFile target)

Read a directory. Returns all the simple path names (excluding "." and ".."). The returned list will be empty if the node is not a directory.

Parameters:

mountPoint - the mount point of the filesystem instance (guaranteed to be a parent of target)

target - the virtual file to act upon

Returns:

the collection of children names

getCodeSigners

CodeSigner[] getCodeSigners(VirtualFile mountPoint,
                          VirtualFile target)

Get the CodeSigners for a the virtual file.

Parameters:

mountPoint - the mount point of the filesystem instance (guaranteed to be a parent of target)

target - the virtual file to act upon

Returns:

CodeSigner for the virtual file or null if not signed.

close

void close()
           throws IOException

Destroy this filesystem instance. After this method is called, the filesystem may not be used in any way. This method should be called only after all mounts of this filesystem have been cleared; otherwise, VFS accesses may result in IOExceptions.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException - if an I/O error occurs during close

getMountSource

File getMountSource()

Get the File source provided at mount time.

Returns:

the source used for mounting

getRootURI

URI getRootURI()
               throws URISyntaxException

Get the root URI for this file system, or null if there is no valid root URI.

Returns:

the root URI

Throws:

URISyntaxException - if the URI isn't valid