java.io
Class FileSystem

java.lang.Object
  java.io.FileSystem

Direct Known Subclasses:

Win32FileSystem

abstract class FileSystem

extends Object

Package-private abstract class for the local filesystem abstraction.

Field Summary

static int	BA_DIRECTORY
static int	BA_EXISTS
static int	BA_HIDDEN
static int	BA_REGULAR
(package private) static boolean	useCanonCaches
(package private) static boolean	useCanonPrefixCache

Constructor Summary

(package private)

FileSystem()

Method Summary

abstract String	canonicalize(String path)
abstract boolean	checkAccess(File f, boolean write) Check whether the file or directory denoted by the given abstract pathname may be accessed by this process.
abstract int	compare(File f1, File f2) Compare two abstract pathnames lexicographically.
abstract boolean	createDirectory(File f) Create a new directory denoted by the given abstract pathname, returning true if and only if the operation succeeds.
abstract boolean	createFileExclusively(String pathname) Create a new empty file with the given pathname.
abstract boolean	delete(File f) Delete the file or directory denoted by the given abstract pathname, returning true if and only if the operation succeeds.
abstract boolean	deleteOnExit(File f) Arrange for the file or directory denoted by the given abstract pathname to be deleted when the VM exits, returning true if and only if the operation succeeds.
abstract String	fromURIPath(String path) Post-process the given URI path string if necessary.
abstract int	getBooleanAttributes(File f) Return the simple boolean attributes for the file or directory denoted by the given abstract pathname, or zero if it does not exist or some other I/O error occurs.
private static boolean	getBooleanProperty(String prop, boolean defaultVal)
abstract String	getDefaultParent() Return the parent pathname string to be used when the parent-directory argument in one of the two-argument File constructors is the empty pathname.
static FileSystem	getFileSystem() Return the FileSystem object representing this platform's local filesystem.
abstract long	getLastModifiedTime(File f) Return the time at which the file or directory denoted by the given abstract pathname was last modified, or zero if it does not exist or some other I/O error occurs.
abstract long	getLength(File f) Return the length in bytes of the file denoted by the given abstract pathname, or zero if it does not exist, is a directory, or some other I/O error occurs.
abstract char	getPathSeparator() Return the local filesystem's path-separator character.
abstract char	getSeparator() Return the local filesystem's name-separator character.
abstract int	hashCode(File f) Compute the hash code of an abstract pathname.
abstract boolean	isAbsolute(File f) Tell whether or not the given abstract pathname is absolute.
abstract String[]	list(File f) List the elements of the directory denoted by the given abstract pathname.
abstract File[]	listRoots() List the available filesystem roots.
abstract String	normalize(String path) Convert the given pathname string to normal form.
abstract int	prefixLength(String path) Compute the length of this pathname string's prefix.
abstract boolean	rename(File f1, File f2) Rename the file or directory denoted by the first abstract pathname to the second abstract pathname, returning true if and only if the operation succeeds.
abstract String	resolve(File f) Resolve the given abstract pathname into absolute form.
abstract String	resolve(String parent, String child) Resolve the child pathname string against the parent.
abstract boolean	setLastModifiedTime(File f, long time) Set the last-modified time of the file or directory denoted by the given abstract pathname, returning true if and only if the operation succeeds.
abstract boolean	setReadOnly(File f) Mark the file or directory denoted by the given abstract pathname as read-only, returning true if and only if the operation succeeds.

Methods inherited from class java.lang.Object

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

Field Detail

BA_EXISTS

public static final int BA_EXISTS

See Also:

Constant Field Values

BA_REGULAR

public static final int BA_REGULAR

See Also:

Constant Field Values

BA_DIRECTORY

public static final int BA_DIRECTORY

See Also:

Constant Field Values

BA_HIDDEN

public static final int BA_HIDDEN

See Also:

Constant Field Values

useCanonCaches

static boolean useCanonCaches

useCanonPrefixCache

static boolean useCanonPrefixCache

Constructor Detail

FileSystem

FileSystem()

Method Detail

getFileSystem

public static FileSystem getFileSystem()

Return the FileSystem object representing this platform's local filesystem.

getSeparator

public abstract char getSeparator()

Return the local filesystem's name-separator character.

getPathSeparator

public abstract char getPathSeparator()

Return the local filesystem's path-separator character.

normalize

public abstract String normalize(String path)

Convert the given pathname string to normal form. If the string is already in normal form then it is simply returned.

prefixLength

public abstract int prefixLength(String path)

Compute the length of this pathname string's prefix. The pathname string must be in normal form.

resolve

public abstract String resolve(String parent,
                               String child)

Resolve the child pathname string against the parent. Both strings must be in normal form, and the result will be in normal form.

getDefaultParent

public abstract String getDefaultParent()

Return the parent pathname string to be used when the parent-directory argument in one of the two-argument File constructors is the empty pathname.

fromURIPath

public abstract String fromURIPath(String path)

Post-process the given URI path string if necessary. This is used on win32, e.g., to transform "/c:/foo" into "c:/foo". The path string still has slash separators; code in the File class will translate them after this method returns.

isAbsolute

public abstract boolean isAbsolute(File f)

Tell whether or not the given abstract pathname is absolute.

resolve

public abstract String resolve(File f)

Resolve the given abstract pathname into absolute form. Invoked by the getAbsolutePath and getCanonicalPath methods in the File class.

canonicalize

public abstract String canonicalize(String path)
                             throws IOException

Throws:

IOException

getBooleanAttributes

public abstract int getBooleanAttributes(File f)

Return the simple boolean attributes for the file or directory denoted by the given abstract pathname, or zero if it does not exist or some other I/O error occurs.

checkAccess

public abstract boolean checkAccess(File f,
                                    boolean write)

Check whether the file or directory denoted by the given abstract pathname may be accessed by this process. If the second argument is false, then a check for read access is made; if the second argument is true, then a check for write (not read-write) access is made. Return false if access is denied or an I/O error occurs.

getLastModifiedTime

public abstract long getLastModifiedTime(File f)

Return the time at which the file or directory denoted by the given abstract pathname was last modified, or zero if it does not exist or some other I/O error occurs.

getLength

public abstract long getLength(File f)

Return the length in bytes of the file denoted by the given abstract pathname, or zero if it does not exist, is a directory, or some other I/O error occurs.

createFileExclusively

public abstract boolean createFileExclusively(String pathname)
                                       throws IOException

Create a new empty file with the given pathname. Return true if the file was created and false if a file or directory with the given pathname already exists. Throw an IOException if an I/O error occurs.

Throws:

IOException

delete

public abstract boolean delete(File f)

Delete the file or directory denoted by the given abstract pathname, returning true if and only if the operation succeeds.

deleteOnExit

public abstract boolean deleteOnExit(File f)

Arrange for the file or directory denoted by the given abstract pathname to be deleted when the VM exits, returning true if and only if the operation succeeds.

list

public abstract String[] list(File f)

List the elements of the directory denoted by the given abstract pathname. Return an array of strings naming the elements of the directory if successful; otherwise, return null.

createDirectory

public abstract boolean createDirectory(File f)

Create a new directory denoted by the given abstract pathname, returning true if and only if the operation succeeds.

rename

public abstract boolean rename(File f1,
                               File f2)

Rename the file or directory denoted by the first abstract pathname to the second abstract pathname, returning true if and only if the operation succeeds.

setLastModifiedTime

public abstract boolean setLastModifiedTime(File f,
                                            long time)

Set the last-modified time of the file or directory denoted by the given abstract pathname, returning true if and only if the operation succeeds.

setReadOnly

public abstract boolean setReadOnly(File f)

Mark the file or directory denoted by the given abstract pathname as read-only, returning true if and only if the operation succeeds.

listRoots

public abstract File[] listRoots()

List the available filesystem roots.

compare

public abstract int compare(File f1,
                            File f2)

Compare two abstract pathnames lexicographically.

hashCode

public abstract int hashCode(File f)

Compute the hash code of an abstract pathname.

getBooleanProperty

private static boolean getBooleanProperty(String prop,
                                          boolean defaultVal)