Class FileDialog

java.lang.Object

java.awt.Component

java.awt.Container

java.awt.Window

java.awt.Dialog

java.awt.FileDialog

All Implemented Interfaces:

ImageObserver, MenuContainer, Serializable, Accessible

public class FileDialog
extends Dialog

The FileDialog class displays a dialog window from which the user can select a file.

Since it is a modal dialog, when the application calls its show method to display the dialog, it blocks the rest of the application until the user has chosen a file.

Since:

1.0

See Also:

• Window.show()
• Serialized Form

Nested Class Summary

Nested classes/interfaces declared in class java.awt.Dialog

Dialog.AccessibleAWTDialog, Dialog.ModalExclusionType, Dialog.ModalityType

Nested classes/interfaces declared in class java.awt.Window

Window.AccessibleAWTWindow, Window.Type

Nested classes/interfaces declared in class java.awt.Container

Container.AccessibleAWTContainer

Nested classes/interfaces declared in class java.awt.Component

Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy

Field Summary

Fields

Modifier and Type	Field	Description
static final int	LOAD	This constant value indicates that the purpose of the file dialog window is to locate a file from which to read.
static final int	SAVE	This constant value indicates that the purpose of the file dialog window is to locate a file to which to write.

Fields declared in class java.awt.Dialog

DEFAULT_MODALITY_TYPE

Fields declared in class java.awt.Component

accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields declared in interface java.awt.image.ImageObserver

ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH

Constructor Summary

Constructors

Constructor	Description
FileDialog(Dialog parent)	Creates a file dialog for loading a file.
FileDialog(Dialog parent, String title)	Creates a file dialog window with the specified title for loading a file.
FileDialog(Dialog parent, String title, int mode)	Creates a file dialog window with the specified title for loading or saving a file.
FileDialog(Frame parent)	Creates a file dialog for loading a file.
FileDialog(Frame parent, String title)	Creates a file dialog window with the specified title for loading a file.
FileDialog(Frame parent, String title, int mode)	Creates a file dialog window with the specified title for loading or saving a file.

Method Summary

Modifier and Type	Method	Description
void	addNotify()	Creates the file dialog's peer.
String	getDirectory()	Gets the directory of this file dialog.
String	getFile()	Gets the selected file of this file dialog.
FilenameFilter	getFilenameFilter()	Determines this file dialog's filename filter.
File[]	getFiles()	Returns files that the user selects.
int	getMode()	Indicates whether this file dialog box is for loading from a file or for saving to a file.
boolean	isMultipleMode()	Returns whether the file dialog allows the multiple file selection.
protected String	paramString()	Returns a string representing the state of this FileDialog window.
void	setDirectory(String dir)	Sets the directory of this file dialog window to be the specified directory.
void	setFile(String file)	Sets the selected file for this file dialog window to be the specified file.
void	setFilenameFilter(FilenameFilter filter)	Sets the filename filter for this file dialog window to the specified filter.
void	setMode(int mode)	Sets the mode of the file dialog.
void	setMultipleMode(boolean enable)	Enables or disables multiple file selection for the file dialog.
void	setTitle(String title)	Sets the title of the Dialog.

Methods declared in class java.awt.Dialog

getAccessibleContext, getModalityType, getTitle, hide, isModal, isResizable, isUndecorated, setModal, setModalityType, setResizable, setUndecorated, setVisible, show, toBack

Methods declared in class java.awt.Window

addPropertyChangeListener, addPropertyChangeListener, addWindowFocusListener, addWindowListener, addWindowStateListener, applyResourceBundle, applyResourceBundle, createBufferStrategy, createBufferStrategy, dispose, getBackground, getBufferStrategy, getFocusableWindowState, getFocusCycleRootAncestor, getFocusOwner, getFocusTraversalKeys, getIconImages, getInputContext, getListeners, getLocale, getModalExclusionType, getMostRecentFocusOwner, getOpacity, getOwnedWindows, getOwner, getOwnerlessWindows, getShape, getToolkit, getType, getWarningString, getWindowFocusListeners, getWindowListeners, getWindows, getWindowStateListeners, isActive, isAlwaysOnTop, isAlwaysOnTopSupported, isAutoRequestFocus, isFocusableWindow, isFocusCycleRoot, isFocused, isLocationByPlatform, isOpaque, isShowing, isValidateRoot, pack, paint, postEvent, processEvent, processWindowEvent, processWindowFocusEvent, processWindowStateEvent, removeWindowFocusListener, removeWindowListener, removeWindowStateListener, reshape, setAlwaysOnTop, setAutoRequestFocus, setBackground, setBounds, setBounds, setCursor, setFocusableWindowState, setFocusCycleRoot, setIconImage, setIconImages, setLocation, setLocation, setLocationByPlatform, setLocationRelativeTo, setMinimumSize, setModalExclusionType, setOpacity, setShape, setSize, setSize, setType, toFront

Methods declared in class java.awt.Container

add, add, add, add, add, addContainerListener, addImpl, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getAlignmentX, getAlignmentY, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getComponentZOrder, getContainerListeners, getFocusTraversalPolicy, getInsets, getLayout, getMaximumSize, getMinimumSize, getMousePosition, getPreferredSize, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paintComponents, preferredSize, print, printComponents, processContainerEvent, remove, remove, removeAll, removeContainerListener, removeNotify, setComponentZOrder, setFocusTraversalKeys, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setFont, setLayout, transferFocusDownCycle, update, validate, validateTree

Methods declared in class java.awt.Component

action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, createVolatileImage, createVolatileImage, disable, disableEvents, dispatchEvent, enable, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getBaseline, getBaselineResizeBehavior, getBounds, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getFontMetrics, getForeground, getGraphics, getGraphicsConfiguration, getHeight, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocation, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getSize, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isDoubleBuffered, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isPreferredSizeSet, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, prepareImage, prepareImage, printAll, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, requestFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, requestFocusInWindow, resize, resize, revalidate, setComponentOrientation, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeysEnabled, setForeground, setIgnoreRepaint, setLocale, setMaximumSize, setMixingCutoutShape, setName, setPreferredSize, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle

Methods declared in class java.lang.Object

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

Field Details

LOAD

@Native
public static final int LOAD

This constant value indicates that the purpose of the file dialog window is to locate a file from which to read.

See Also:

• Constant Field Values

SAVE

@Native
public static final int SAVE

This constant value indicates that the purpose of the file dialog window is to locate a file to which to write.

See Also:

• Constant Field Values

Constructor Details

FileDialog

public FileDialog(Frame parent)

Creates a file dialog for loading a file. The title of the file dialog is initially empty. This is a convenience method for FileDialog(parent, "", LOAD).

Note: Some platforms may not support showing the user-specified title in a file dialog. In this situation, either no title will be displayed in the file dialog's title bar or, on some systems, the file dialog's title bar will not be displayed.

Parameters:

parent - the owner of the dialog

Since:

1.1

FileDialog

public FileDialog(Frame parent,
 String title)

Creates a file dialog window with the specified title for loading a file. The files shown are those in the current directory. This is a convenience method for FileDialog(parent, title, LOAD).

Note: Some platforms may not support showing the user-specified title in a file dialog. In this situation, either no title will be displayed in the file dialog's title bar or, on some systems, the file dialog's title bar will not be displayed.

Parameters:

parent - the owner of the dialog

title - the title of the dialog

FileDialog

public FileDialog(Frame parent,
 String title,
 int mode)

Creates a file dialog window with the specified title for loading or saving a file.

If the value of mode is LOAD, then the file dialog is finding a file to read, and the files shown are those in the current directory. If the value of mode is SAVE, the file dialog is finding a place to write a file.

Note: Some platforms may not support showing the user-specified title in a file dialog. In this situation, either no title will be displayed in the file dialog's title bar or, on some systems, the file dialog's title bar will not be displayed.

Parameters:

parent - the owner of the dialog

title - the title of the dialog

mode - the mode of the dialog; either FileDialog.LOAD or FileDialog.SAVE

Throws:

IllegalArgumentException - if an illegal file dialog mode is supplied

See Also:

• LOAD
• SAVE

FileDialog

public FileDialog(Dialog parent)

Creates a file dialog for loading a file. The title of the file dialog is initially empty. This is a convenience method for FileDialog(parent, "", LOAD).

Note: Some platforms may not support showing the user-specified title in a file dialog. In this situation, either no title will be displayed in the file dialog's title bar or, on some systems, the file dialog's title bar will not be displayed.

Parameters:

parent - the owner of the dialog

Throws:

IllegalArgumentException - if the parent's GraphicsConfiguration is not from a screen device;

IllegalArgumentException - if parent is null; this exception is always thrown when GraphicsEnvironment.isHeadless returns true

Since:

1.5

See Also:

• GraphicsEnvironment.isHeadless()

FileDialog

public FileDialog(Dialog parent,
 String title)

Creates a file dialog window with the specified title for loading a file. The files shown are those in the current directory. This is a convenience method for FileDialog(parent, title, LOAD).

Note: Some platforms may not support showing the user-specified title in a file dialog. In this situation, either no title will be displayed in the file dialog's title bar or, on some systems, the file dialog's title bar will not be displayed.

Parameters:

parent - the owner of the dialog

title - the title of the dialog; a null value will be accepted without causing a NullPointerException to be thrown

Throws:

IllegalArgumentException - if the parent's GraphicsConfiguration is not from a screen device;

IllegalArgumentException - if parent is null; this exception is always thrown when GraphicsEnvironment.isHeadless returns true

Since:

1.5

See Also:

• GraphicsEnvironment.isHeadless()

FileDialog

public FileDialog(Dialog parent,
 String title,
 int mode)

Creates a file dialog window with the specified title for loading or saving a file.

If the value of mode is LOAD, then the file dialog is finding a file to read, and the files shown are those in the current directory. If the value of mode is SAVE, the file dialog is finding a place to write a file.

Note: Some platforms may not support showing the user-specified title in a file dialog. In this situation, either no title will be displayed in the file dialog's title bar or, on some systems, the file dialog's title bar will not be displayed.

Parameters:

parent - the owner of the dialog

title - the title of the dialog; a null value will be accepted without causing a NullPointerException to be thrown

mode - the mode of the dialog; either FileDialog.LOAD or FileDialog.SAVE

Throws:

IllegalArgumentException - if an illegal file dialog mode is supplied;

IllegalArgumentException - if the parent's GraphicsConfiguration is not from a screen device;

IllegalArgumentException - if parent is null; this exception is always thrown when GraphicsEnvironment.isHeadless returns true

Since:

1.5

See Also:

• GraphicsEnvironment.isHeadless()
• LOAD
• SAVE

Method Details

setTitle

public void setTitle(String title)

Sets the title of the Dialog.

Note: Some platforms may not support showing the user-specified title in a file dialog. In this situation, either no title will be displayed in the file dialog's title bar or, on some systems, the file dialog's title bar will not be displayed.

Overrides:

setTitle in class Dialog

Parameters:

title - the title displayed in the dialog's border; a null value results in an empty title

See Also:

• Dialog.getTitle()

addNotify

public void addNotify()

Creates the file dialog's peer. The peer allows us to change the look of the file dialog without changing its functionality.

Overrides:

addNotify in class Dialog

See Also:

• Component.isDisplayable()
• Container.removeNotify()

getMode

public int getMode()

Indicates whether this file dialog box is for loading from a file or for saving to a file.

Returns:

the mode of this file dialog window, either FileDialog.LOAD or FileDialog.SAVE

See Also:

• LOAD
• SAVE
• setMode(int)

setMode

public void setMode(int mode)

Sets the mode of the file dialog. If mode is not a legal value, an exception will be thrown and mode will not be set.

Parameters:

mode - the mode for this file dialog, either FileDialog.LOAD or FileDialog.SAVE

Throws:

IllegalArgumentException - if an illegal file dialog mode is supplied

Since:

1.1

See Also:

• LOAD
• SAVE
• getMode()

getDirectory

public String getDirectory()

Gets the directory of this file dialog.

Returns:

the (potentially null or invalid) directory of this FileDialog

See Also:

• setDirectory(java.lang.String)

setDirectory

public void setDirectory(String dir)

Sets the directory of this file dialog window to be the specified directory. Specifying a null or an invalid directory implies an implementation-defined default. This default will not be realized, however, until the user has selected a file. Until this point, getDirectory() will return the value passed into this method.

Specifying "" as the directory is exactly equivalent to specifying null as the directory.

Parameters:

dir - the specified directory

See Also:

• getDirectory()

getFile

public String getFile()

Gets the selected file of this file dialog. If the user selected CANCEL, the returned file is null.

Returns:

the currently selected file of this file dialog window, or null if none is selected

See Also:

• setFile(java.lang.String)

getFiles

public File[] getFiles()

Returns files that the user selects.

If the user cancels the file dialog, then the method returns an empty array.

Returns:

files that the user selects or an empty array if the user cancels the file dialog.

Since:

1.7

See Also:

• setFile(String)
• getFile()

setFile

public void setFile(String file)

Sets the selected file for this file dialog window to be the specified file. This file becomes the default file if it is set before the file dialog window is first shown.

When the dialog is shown, the specified file is selected. The kind of selection depends on the file existence, the dialog type, and the native platform. E.g., the file could be highlighted in the file list, or a file name editbox could be populated with the file name.

This method accepts either a full file path, or a file name with an extension if used together with the setDirectory method.

Specifying "" as the file is exactly equivalent to specifying null as the file.

Parameters:

file - the file being set

See Also:

• getFile()
• getFiles()

setMultipleMode

public void setMultipleMode(boolean enable)

Enables or disables multiple file selection for the file dialog.

Parameters:

enable - if true, multiple file selection is enabled; false - disabled.

Since:

1.7

See Also:

• isMultipleMode()

isMultipleMode

public boolean isMultipleMode()

Returns whether the file dialog allows the multiple file selection.

Returns:

true if the file dialog allows the multiple file selection; false otherwise.

Since:

1.7

See Also:

• setMultipleMode(boolean)

getFilenameFilter

public FilenameFilter getFilenameFilter()

Determines this file dialog's filename filter. A filename filter allows the user to specify which files appear in the file dialog window. Filename filters do not function in Sun's reference implementation for Microsoft Windows.

Returns:

this file dialog's filename filter

See Also:

• FilenameFilter
• setFilenameFilter(java.io.FilenameFilter)

setFilenameFilter

public void setFilenameFilter(FilenameFilter filter)

Sets the filename filter for this file dialog window to the specified filter. Filename filters do not function in Sun's reference implementation for Microsoft Windows.

Parameters:

filter - the specified filter

See Also:

• FilenameFilter
• getFilenameFilter()

paramString

protected String paramString()

Returns a string representing the state of this FileDialog window. This method is intended to be used only for debugging purposes, and the content and format of the returned string may vary between implementations. The returned string may be empty but may not be null.

Overrides:

paramString in class Dialog

Returns:

the parameter string of this file dialog window