Module java.desktop

Package javax.swing.filechooser

Class FileSystemView

java.lang.Object

javax.swing.filechooser.FileSystemView

public abstract class FileSystemView
extends Object

FileSystemView is JFileChooser's gateway to the file system. Since the JDK1.1 File API doesn't allow access to such information as root partitions, file type information, or hidden file bits, this class is designed to intuit as much OS-specific file system information as possible.

Java Licensees may want to provide a different implementation of FileSystemView to better handle a given operating system.

Constructor Summary

Constructors

Constructor	Description
FileSystemView()	Constructs a FileSystemView.

Method Summary

Modifier and Type	Method	Description
File	createFileObject(File dir, String filename)	Returns a File object constructed in dir from the given filename.
File	createFileObject(String path)	Returns a File object constructed from the given path string.
protected File	createFileSystemRoot(File f)	Creates a new File object for f with correct behavior for a file system root directory.
abstract File	createNewFolder(File containingDir)	Creates a new folder with a default folder name.
File	getChild(File parent, String fileName)	Returns a File object which is normally constructed with new File(parent, fileName) except when the parent and child are both special folders, in which case the File is a wrapper containing a ShellFolder object.
File[]	getChooserComboBoxFiles()	Returns an array of files representing the values which will be shown in the file chooser selector.
final File[]	getChooserShortcutPanelFiles()	Returns an array of files representing the values to show by default in the file chooser shortcuts panel.
File	getDefaultDirectory()	Return the user's default starting directory for the file chooser.
File[]	getFiles(File dir, boolean useFileHiding)	Gets the list of shown (i.e. not hidden) files.
static FileSystemView	getFileSystemView()	Returns the file system view.
File	getHomeDirectory()	Returns the home directory.
File	getLinkLocation(File file)	Returns the regular file referenced by the specified link file if the specified file is a shell interpreted link.
File	getParentDirectory(File dir)	Returns the parent directory of dir.
File[]	getRoots()	Returns all root partitions on this system.
String	getSystemDisplayName(File f)	Name of a file, directory, or folder as it would be displayed in a system file browser.
Icon	getSystemIcon(File f)	Icon for a file, directory, or folder as it would be displayed in a system file browser.
Icon	getSystemIcon(File f, int width, int height)	Returns an icon for a file, directory, or folder as it would be displayed in a system file browser for the requested size.
String	getSystemTypeDescription(File f)	Type description for a file, directory, or folder as it would be displayed in a system file browser.
boolean	isComputerNode(File dir)	Used by UI classes to decide whether to display a special icon for a computer node, e.g.
boolean	isDrive(File dir)	Used by UI classes to decide whether to display a special icon for drives or partitions, e.g. a "hard disk" icon.
boolean	isFileSystem(File f)	Checks if f represents a real directory or file as opposed to a special folder such as "Desktop".
boolean	isFileSystemRoot(File dir)	Is dir the root of a tree in the file system, such as a drive or partition.
boolean	isFloppyDrive(File dir)	Used by UI classes to decide whether to display a special icon for a floppy disk.
boolean	isHiddenFile(File f)	Returns whether a file is hidden or not.
boolean	isLink(File file)	Returns whether the specified file denotes a shell interpreted link which can be obtained by the getLinkLocation(File).
boolean	isParent(File folder, File file)	On Windows, a file can appear in multiple folders, other than its parent directory in the filesystem.
boolean	isRoot(File f)	Determines if the given file is a root in the navigable tree(s).
Boolean	isTraversable(File f)	Returns true if the file (directory) can be visited.

Methods declared in class java.lang.Object

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

Constructor Details

FileSystemView

public FileSystemView()

Constructs a FileSystemView.

Method Details

getFileSystemView

public static FileSystemView getFileSystemView()

Returns the file system view.

Returns:

the file system view

isRoot

public boolean isRoot(File f)

Determines if the given file is a root in the navigable tree(s). Examples: Windows 98 has one root, the Desktop folder. DOS has one root per drive letter, C:\, D:\, etc. Unix has one root, the "/" directory. The default implementation gets information from the ShellFolder class.

Parameters:

f - a File object representing a directory

Returns:

true if f is a root in the navigable tree.

See Also:

• isFileSystemRoot(java.io.File)

isTraversable

public Boolean isTraversable(File f)

Returns true if the file (directory) can be visited. Returns false if the directory cannot be traversed.

Parameters:

f - the File

Returns:

true if the file/directory can be traversed, otherwise false

Since:

1.4

See Also:

• JFileChooser.isTraversable(java.io.File)
• FileView.isTraversable(java.io.File)

getSystemDisplayName

public String getSystemDisplayName(File f)

Name of a file, directory, or folder as it would be displayed in a system file browser. Example from Windows: the "M:\" directory displays as "CD-ROM (M:)" The default implementation gets information from the ShellFolder class.

Parameters:

f - a File object

Returns:

the file name as it would be displayed by a native file chooser

Since:

1.4

See Also:

• JFileChooser.getName(java.io.File)

getSystemTypeDescription

public String getSystemTypeDescription(File f)

Type description for a file, directory, or folder as it would be displayed in a system file browser. Example from Windows: the "Desktop" folder is described as "Desktop". Override for platforms with native ShellFolder implementations.

Parameters:

f - a File object

Returns:

the file type description as it would be displayed by a native file chooser or null if no native information is available.

Since:

1.4

See Also:

• JFileChooser.getTypeDescription(java.io.File)

getSystemIcon

public Icon getSystemIcon(File f)

Icon for a file, directory, or folder as it would be displayed in a system file browser. Example from Windows: the "M:\" directory displays a CD-ROM icon.

The default implementation gets information from the ShellFolder class.

Parameters:

f - a File object

Returns:

an icon as it would be displayed by a native file chooser

Since:

1.4

See Also:

• JFileChooser.getIcon(java.io.File)

getSystemIcon

public Icon getSystemIcon(File f,
 int width,
 int height)

Returns an icon for a file, directory, or folder as it would be displayed in a system file browser for the requested size.

Example:

     FileSystemView fsv = FileSystemView.getFileSystemView();
     Icon icon = fsv.getSystemIcon(new File("application.exe"), 64, 64);
     JLabel label = new JLabel(icon);
 

Implementation Requirements:

The available icons may be platform specific and so the available sizes determined by the platform. Therefore an exact match for the requested size may not be possible. The icon returned may be a multi-resolution icon image, which allows better support for High DPI environments with different scaling factors.

Parameters:

f - a File object for which the icon will be retrieved

width - width of the icon in user coordinate system.

height - height of the icon in user coordinate system.

Returns:

an icon as it would be displayed by a native file chooser or null for a non-existent or inaccessible file.

Throws:

IllegalArgumentException - if an invalid parameter such as a negative size or a null file reference is passed.

Since:

17

See Also:

• JFileChooser.getIcon(java.io.File)
• AbstractMultiResolutionImage
• getSystemIcon(File)

isParent

public boolean isParent(File folder,
 File file)

On Windows, a file can appear in multiple folders, other than its parent directory in the filesystem. Folder could for example be the "Desktop" folder which is not the same as file.getParentFile().

Parameters:

folder - a File object representing a directory or special folder

file - a File object

Returns:

true if folder is a directory or special folder and contains file.

Since:

1.4

getChild

public File getChild(File parent,
 String fileName)

Returns a File object which is normally constructed with new File(parent, fileName) except when the parent and child are both special folders, in which case the File is a wrapper containing a ShellFolder object.

Parameters:

parent - a File object representing a directory or special folder

fileName - a name of a file or folder which exists in parent

Returns:

a File object.

Since:

1.4

isFileSystem

public boolean isFileSystem(File f)

Checks if f represents a real directory or file as opposed to a special folder such as "Desktop". Used by UI classes to decide if a folder is selectable when doing directory choosing.

Parameters:

f - a File object

Returns:

true if f is a real file or directory.

Since:

1.4

createNewFolder

public abstract File createNewFolder(File containingDir)
                              throws IOException

Creates a new folder with a default folder name.

Parameters:

containingDir - a File object denoting directory to contain the new folder

Returns:

a File object denoting the newly created folder

Throws:

IOException - if new folder could not be created

isHiddenFile

public boolean isHiddenFile(File f)

Returns whether a file is hidden or not.

Parameters:

f - a File object

Returns:

true if the given File denotes a hidden file

isFileSystemRoot

public boolean isFileSystemRoot(File dir)

Is dir the root of a tree in the file system, such as a drive or partition. Example: Returns true for "C:\" on Windows 98.

Parameters:

dir - a File object representing a directory

Returns:

true if f is a root of a filesystem

Since:

1.4

See Also:

• isRoot(java.io.File)

isDrive

public boolean isDrive(File dir)

Used by UI classes to decide whether to display a special icon for drives or partitions, e.g. a "hard disk" icon. The default implementation has no way of knowing, so always returns false.

Parameters:

dir - a directory

Returns:

false always

Since:

1.4

isFloppyDrive

public boolean isFloppyDrive(File dir)

Used by UI classes to decide whether to display a special icon for a floppy disk. Implies isDrive(dir). The default implementation has no way of knowing, so always returns false.

Parameters:

dir - a directory

Returns:

false always

Since:

1.4

isComputerNode

public boolean isComputerNode(File dir)

Used by UI classes to decide whether to display a special icon for a computer node, e.g. "My Computer" or a network server. The default implementation has no way of knowing, so always returns false.

Parameters:

dir - a directory

Returns:

false always

Since:

1.4

getRoots

public File[] getRoots()

Returns all root partitions on this system. For example, on Windows, this would be the "Desktop" folder, while on DOS this would be the A: through Z: drives.

Returns:

an array of File objects representing all root partitions on this system

getHomeDirectory

public File getHomeDirectory()

Returns the home directory.

Returns:

the home directory

getDefaultDirectory

public File getDefaultDirectory()

Return the user's default starting directory for the file chooser.

Returns:

a File object representing the default starting folder

Since:

1.4

createFileObject

public File createFileObject(File dir,
 String filename)

Returns a File object constructed in dir from the given filename.

Parameters:

dir - an abstract pathname denoting a directory

filename - a String representation of a pathname

Returns:

a File object created from dir and filename

createFileObject

public File createFileObject(String path)

Returns a File object constructed from the given path string.

Parameters:

path - String representation of path

Returns:

a File object created from the given path

getFiles

public File[] getFiles(File dir,
 boolean useFileHiding)

Gets the list of shown (i.e. not hidden) files.

Parameters:

dir - the root directory of files to be returned

useFileHiding - determine if hidden files are returned

Returns:

an array of File objects representing files and directories in the given dir. It includes hidden files if useFileHiding is false.

getParentDirectory

public File getParentDirectory(File dir)

Returns the parent directory of dir.

Parameters:

dir - the File being queried

Returns:

the parent directory of dir, or null if dir is null

getChooserComboBoxFiles

public File[] getChooserComboBoxFiles()

Returns an array of files representing the values which will be shown in the file chooser selector.

Returns:

an array of File objects. The array returned may be possibly empty if there are no appropriate permissions.

Since:

9

getChooserShortcutPanelFiles

public final File[] getChooserShortcutPanelFiles()

Returns an array of files representing the values to show by default in the file chooser shortcuts panel.

Returns:

an array of File objects. The array returned may be possibly empty if there are no appropriate permissions.

Since:

12

isLink

public boolean isLink(File file)

Returns whether the specified file denotes a shell interpreted link which can be obtained by the getLinkLocation(File).

Parameters:

file - a file

Returns:

whether this is a link

Throws:

NullPointerException - if file equals null

SecurityException - if the caller does not have necessary permissions

Since:

9

See Also:

• getLinkLocation(File)

getLinkLocation

public File getLinkLocation(File file)
                     throws FileNotFoundException

Returns the regular file referenced by the specified link file if the specified file is a shell interpreted link. Returns null if the specified file is not a shell interpreted link.

Parameters:

file - a file

Returns:

the linked file or null.

Throws:

FileNotFoundException - if the linked file does not exist

NullPointerException - if file equals null

SecurityException - if the caller does not have necessary permissions

Since:

9

createFileSystemRoot

protected File createFileSystemRoot(File f)

Creates a new File object for f with correct behavior for a file system root directory.

Parameters:

f - a File object representing a file system root directory, for example "/" on Unix or "C:\" on Windows.

Returns:

a new File object

Since:

1.4