W3cubDocs

Class Toolkit

java.lang.Object

java.awt.Toolkit

public abstract class Toolkit extends Object

This class is the abstract superclass of all actual implementations of the Abstract Window Toolkit. Subclasses of the Toolkit class are used to bind the various components to particular native toolkit implementations.

Many GUI events may be delivered to user asynchronously, if the opposite is not specified explicitly. As well as many GUI operations may be performed asynchronously. This fact means that if the state of a component is set, and then the state immediately queried, the returned value may not yet reflect the requested change. This behavior includes, but is not limited to:

Scrolling to a specified position.
For example, calling ScrollPane.setScrollPosition and then getScrollPosition may return an incorrect value if the original request has not yet been processed.
Moving the focus from one component to another.
For more information, see Timing Focus Transfers, a section in The Swing Tutorial.
Making a top-level container visible.
Calling setVisible(true) on a Window, Frame or Dialog may occur asynchronously.
Setting the size or location of a top-level container.
Calls to setSize, setBounds or setLocation on a Window, Frame or Dialog are forwarded to the underlying window management system and may be ignored or modified. See Window for more information.

Most applications should not call any of the methods in this class directly. The methods defined by Toolkit are the "glue" that joins the platform-independent classes in the java.awt package with their counterparts in java.awt.peer. Some methods defined by Toolkit query the native operating system directly.

Since:: 1.0

Field Summary

Modifier and Type	Field	Description
`protected final Map<String,Object>`	`desktopProperties`	The desktop properties.
`protected final PropertyChangeSupport`	`desktopPropsSupport`	The desktop properties change support.

Constructor Summary

Toolkit()

Modifier	Constructor	Description
`protected`	Constructs a `Toolkit`.

Method Summary

Modifier and Type	Method	Description
`void`	`addAWTEventListener(AWTEventListener listener, long eventMask)`	Adds an AWTEventListener to receive all AWTEvents dispatched system-wide that conform to the given `eventMask`.
`void`	`addPropertyChangeListener(String name, PropertyChangeListener pcl)`	Adds the specified property change listener for the named desktop property.
`boolean`	`areExtraMouseButtonsEnabled()`	Reports whether events from extra mouse buttons are allowed to be processed and posted into `EventQueue`.
`abstract void`	`beep()`	Emits an audio beep depending on native system settings and hardware capabilities.
`abstract int`	`checkImage(Image image, int width, int height, ImageObserver observer)`	Indicates the construction status of a specified image that is being prepared for display.
`Cursor`	`createCustomCursor(Image cursor, Point hotSpot, String name)`	Creates a new custom cursor object.
`<T extends DragGestureRecognizer> T`	`createDragGestureRecognizer(Class<T> abstractRecognizerClass, DragSource ds, Component c, int srcActions, DragGestureListener dgl)`	Creates a concrete, platform dependent, subclass of the abstract DragGestureRecognizer class requested, and associates it with the DragSource, Component and DragGestureListener specified.
`Image`	`createImage(byte[] imagedata)`	Creates an image which decodes the image stored in the specified byte array.
`abstract Image`	`createImage(byte[] imagedata, int imageoffset, int imagelength)`	Creates an image which decodes the image stored in the specified byte array, and at the specified offset and length.
`abstract Image`	`createImage(ImageProducer producer)`	Creates an image with the specified image producer.
`abstract Image`	`createImage(String filename)`	Returns an image which gets pixel data from the specified file.
`abstract Image`	`createImage(URL url)`	Returns an image which gets pixel data from the specified URL.
`AWTEventListener[]`	`getAWTEventListeners()`	Returns an array of all the `AWTEventListener`s registered on this toolkit.
`AWTEventListener[]`	`getAWTEventListeners(long eventMask)`	Returns an array of all the `AWTEventListener`s registered on this toolkit which listen to all of the event types specified in the `eventMask` argument.
`Dimension`	`getBestCursorSize(int preferredWidth, int preferredHeight)`	Returns the supported cursor dimension which is closest to the desired sizes.
`abstract ColorModel`	`getColorModel()`	Determines the color model of this toolkit's screen.
`static Toolkit`	`getDefaultToolkit()`	Gets the default toolkit.
`final Object`	`getDesktopProperty(String propertyName)`	Obtains a value for the specified desktop property.
`abstract String[]`	`getFontList()`	Deprecated. see `GraphicsEnvironment.getAvailableFontFamilyNames()`
`abstract FontMetrics`	`getFontMetrics(Font font)`	Deprecated. As of JDK version 1.2, replaced by the `Font` method `getLineMetrics`.
`abstract Image`	`getImage(String filename)`	Returns an image which gets pixel data from the specified file, whose format can be either GIF, JPEG or PNG.
`abstract Image`	`getImage(URL url)`	Returns an image which gets pixel data from the specified URL.
`boolean`	`getLockingKeyState(int keyCode)`	Returns whether the given locking key on the keyboard is currently in its "on" state.
`int`	`getMaximumCursorColors()`	Returns the maximum number of colors the Toolkit supports in a custom cursor palette.
`int`	`getMenuShortcutKeyMask()`	Deprecated. It is recommended that extended modifier keys and `getMenuShortcutKeyMaskEx()` be used instead
`int`	`getMenuShortcutKeyMaskEx()`	Determines which extended modifier key is the appropriate accelerator key for menu shortcuts.
`protected static Container`	`getNativeContainer(Component c)`	Give native peers the ability to query the native container given a native component (eg the direct parent may be lightweight).
`PrintJob`	`getPrintJob(Frame frame, String jobtitle, JobAttributes jobAttributes, PageAttributes pageAttributes)`	Gets a `PrintJob` object which is the result of initiating a print operation on the toolkit's platform.
`abstract PrintJob`	`getPrintJob(Frame frame, String jobtitle, Properties props)`	Gets a `PrintJob` object which is the result of initiating a print operation on the toolkit's platform.
`static String`	`getProperty(String key, String defaultValue)`	Gets a property with the specified key and default.
`PropertyChangeListener[]`	`getPropertyChangeListeners()`	Returns an array of all the property change listeners registered on this toolkit.
`PropertyChangeListener[]`	`getPropertyChangeListeners(String propertyName)`	Returns an array of all property change listeners associated with the specified name of a desktop property.
`Insets`	`getScreenInsets(GraphicsConfiguration gc)`	Gets the insets of the screen.
`abstract int`	`getScreenResolution()`	Returns the screen resolution in dots-per-inch.
`abstract Dimension`	`getScreenSize()`	Gets the size of the screen.
`abstract Clipboard`	`getSystemClipboard()`	Gets the singleton instance of the system Clipboard which interfaces with clipboard facilities provided by the native platform.
`final EventQueue`	`getSystemEventQueue()`	Get the application's or applet's EventQueue instance.
`protected abstract EventQueue`	`getSystemEventQueueImpl()`	Gets the application's or applet's `EventQueue` instance, without checking access.
`Clipboard`	`getSystemSelection()`	Gets the singleton instance of the system selection as a `Clipboard` object.
`protected void`	`initializeDesktopProperties()`	initializeDesktopProperties
`boolean`	`isAlwaysOnTopSupported()`	Returns whether the always-on-top mode is supported by this toolkit.
`boolean`	`isDynamicLayoutActive()`	Returns whether dynamic layout of Containers on resize is currently enabled on the underlying operating system and/or window manager.
`protected boolean`	`isDynamicLayoutSet()`	Returns whether the layout of Containers is validated dynamically during resizing, or statically, after resizing is complete.
`boolean`	`isFrameStateSupported(int state)`	Returns whether Toolkit supports this state for `Frame`s.
`abstract boolean`	`isModalExclusionTypeSupported(Dialog.ModalExclusionType modalExclusionType)`	Returns whether the given modal exclusion type is supported by this toolkit.
`abstract boolean`	`isModalityTypeSupported(Dialog.ModalityType modalityType)`	Returns whether the given modality type is supported by this toolkit.
`protected Object`	`lazilyLoadDesktopProperty(String name)`	An opportunity to lazily evaluate desktop property values.
`protected void`	`loadSystemColors(int[] systemColors)`	Fills in the integer array that is supplied as an argument with the current system color values.
`abstract Map<TextAttribute,?>`	`mapInputMethodHighlight(InputMethodHighlight highlight)`	Returns a map of visual attributes for the abstract level description of the given input method highlight, or null if no mapping is found.
`abstract boolean`	`prepareImage(Image image, int width, int height, ImageObserver observer)`	Prepares an image for rendering.
`void`	`removeAWTEventListener(AWTEventListener listener)`	Removes an AWTEventListener from receiving dispatched AWTEvents.
`void`	`removePropertyChangeListener(String name, PropertyChangeListener pcl)`	Removes the specified property change listener for the named desktop property.
`protected final void`	`setDesktopProperty(String name, Object newValue)`	Sets the named desktop property to the specified value and fires a property change event to notify any listeners that the value has changed.
`void`	`setDynamicLayout(boolean dynamic)`	Controls whether the layout of Containers is validated dynamically during resizing, or statically, after resizing is complete.
`void`	`setLockingKeyState(int keyCode, boolean on)`	Sets the state of the given locking key on the keyboard.
`abstract void`	`sync()`	Synchronizes this toolkit's graphics state.

Methods declared in class java.lang.Object

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

Field Details

desktopProperties

protected final Map<String,Object> desktopProperties

The desktop properties.

desktopPropsSupport

protected final PropertyChangeSupport desktopPropsSupport

The desktop properties change support.

Constructor Details

Toolkit

protected Toolkit()

Constructs a Toolkit.

Method Details

loadSystemColors

protected void loadSystemColors(int[] systemColors) throws HeadlessException

Fills in the integer array that is supplied as an argument with the current system color values.

Parameters:

systemColors - an integer array.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

Since:

1.1

See Also:

setDynamicLayout

public void setDynamicLayout(boolean dynamic) throws HeadlessException

Controls whether the layout of Containers is validated dynamically during resizing, or statically, after resizing is complete. Use isDynamicLayoutActive() to detect if this feature enabled in this program and is supported by this operating system and/or window manager. Note that this feature is supported not on all platforms, and conversely, that this feature cannot be turned off on some platforms. On these platforms where dynamic layout during resizing is not supported (or is always supported), setting this property has no effect. Note that this feature can be set or unset as a property of the operating system or window manager on some platforms. On such platforms, the dynamic resize property must be set at the operating system or window manager level before this method can take effect. This method does not change support or settings of the underlying operating system or window manager. The OS/WM support can be queried using getDesktopProperty("awt.dynamicLayoutSupported") method.

Parameters:

dynamic - If true, Containers should re-layout their components as the Container is being resized. If false, the layout will be validated after resizing is completed.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

Since:

1.4

See Also:

isDynamicLayoutSet

protected boolean isDynamicLayoutSet() throws HeadlessException

Returns whether the layout of Containers is validated dynamically during resizing, or statically, after resizing is complete. Note: this method returns the value that was set programmatically; it does not reflect support at the level of the operating system or window manager for dynamic layout on resizing, or the current operating system or window manager settings. The OS/WM support can be queried using getDesktopProperty("awt.dynamicLayoutSupported").

Returns:

true if validation of Containers is done dynamically, false if validation is done after resizing is finished.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

Since:

1.4

See Also:

isDynamicLayoutActive

public boolean isDynamicLayoutActive() throws HeadlessException

Returns whether dynamic layout of Containers on resize is currently enabled on the underlying operating system and/or window manager. If the platform supports it, setDynamicLayout(boolean) may be used to programmatically enable or disable platform dynamic layout. Regardless of whether that toggling is supported, or whether true or


 false

is specified as an argument, or has never been called at all, this method will return the active current platform behavior and which will be followed by the JDK in determining layout policy during resizing.

If dynamic layout is currently inactive then Containers re-layout their components when resizing is completed. As a result the Component.validate() method will be invoked only once per resize. If dynamic layout is currently active then Containers re-layout their components on every native resize event and the validate() method will be invoked each time. The OS/WM support can be queried using the getDesktopProperty("awt.dynamicLayoutSupported") method. This property will reflect the platform capability but is not sufficient to tell if it is presently enabled.

Returns:

true if dynamic layout of Containers on resize is currently active, false otherwise.

Throws:

HeadlessException - if the GraphicsEnvironment.isHeadless() method returns true

Since:

1.4

See Also:

getScreenSize

public abstract Dimension getScreenSize() throws HeadlessException

Gets the size of the screen. On systems with multiple displays, the primary display is used. Multi-screen aware display dimensions are available from GraphicsConfiguration and GraphicsDevice.

Returns:

the size of this toolkit's screen, in pixels.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

See Also:

getScreenResolution

public abstract int getScreenResolution() throws HeadlessException

Returns the screen resolution in dots-per-inch.

Returns:

this toolkit's screen resolution, in dots-per-inch.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

See Also:

getScreenInsets

public Insets getScreenInsets(GraphicsConfiguration gc) throws HeadlessException

Gets the insets of the screen.

Parameters:

gc - a GraphicsConfiguration

Returns:

the insets of this toolkit's screen, in pixels.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

Since:

1.4

See Also:

getColorModel

public abstract ColorModel getColorModel() throws HeadlessException

Determines the color model of this toolkit's screen.

ColorModel is an abstract class that encapsulates the ability to translate between the pixel values of an image and its red, green, blue, and alpha components.

This toolkit method is called by the getColorModel method of the Component class.

Returns:

the color model of this toolkit's screen.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

See Also:

getFontList

@Deprecated public abstract String[] getFontList()

Deprecated.

see GraphicsEnvironment.getAvailableFontFamilyNames()

Returns the names of the available fonts in this toolkit.

For 1.1, the following font names are deprecated (the replacement name follows):

TimesRoman (use Serif)
Helvetica (use SansSerif)
Courier (use Monospaced)

The ZapfDingbats fontname is also deprecated in 1.1 but the characters are defined in Unicode starting at 0x2700, and as of 1.1 Java supports those characters.

Returns:

the names of the available fonts in this toolkit.

See Also:

getFontMetrics

@Deprecated public abstract FontMetrics getFontMetrics(Font font)

Deprecated.

As of JDK version 1.2, replaced by the Font method getLineMetrics.

Gets the screen device metrics for rendering of the font.

Parameters:

font - a font

Returns:

the screen metrics of the specified font in this toolkit

See Also:

sync

public abstract void sync()

Synchronizes this toolkit's graphics state. Some window systems may do buffering of graphics events.

This method ensures that the display is up-to-date. It is useful for animation.

getDefaultToolkit

public static Toolkit getDefaultToolkit()

Gets the default toolkit.

If a system property named "java.awt.headless" is set to true then the headless implementation of Toolkit is used, otherwise the default platform-specific implementation of Toolkit is used.

If this Toolkit is not a headless implementation and if they exist, service providers of AccessibilityProvider will be loaded if specified by the system property javax.accessibility.assistive_technologies.

An example of setting this property is to invoke Java with -Djavax.accessibility.assistive_technologies=MyServiceProvider. In addition to MyServiceProvider other service providers can be specified using a comma separated list. Service providers are loaded after the AWT toolkit is created.

If the list of assistive technology providers as provided through system property "javax.accessibility.assistive_technologies" is the empty string or contains only white space characters it is ignored. All other errors are handled via an AWTError exception.

The names specified in the assistive_technologies property are used to query each service provider implementation. If the requested name matches the name of the service provider, the AccessibilityProvider.activate() method will be invoked to activate the matching service provider.

Implementation Requirements:

If assistive technology service providers are not specified with a system property this implementation will look in a properties file located as follows:

${user.home}/.accessibility.properties
${java.home}/conf/accessibility.properties

Only the first of these files to be located will be consulted. The requested service providers are specified by setting the assistive_technologies= property. A single provider or a comma separated list of providers can be specified.

Returns:

the default toolkit.

Throws:

AWTError - in case of an error loading assistive technologies.

See Also:

getImage

public abstract Image getImage(String filename)

Returns an image which gets pixel data from the specified file, whose format can be either GIF, JPEG or PNG. The underlying toolkit attempts to resolve multiple requests with the same filename to the same returned Image.

Since the mechanism required to facilitate this sharing of Image objects may continue to hold onto images that are no longer in use for an indefinite period of time, developers are encouraged to implement their own caching of images by using the createImage variant wherever available. If the image data contained in the specified file changes, the Image object returned from this method may still contain stale information which was loaded from the file after a prior call. Previously loaded image data can be manually discarded by calling the flush method on the returned Image.

This method first checks if there is a security manager installed. If so, the method calls the security manager's checkRead method with the file specified to ensure that the access to the image is allowed.

Parameters:

filename - the name of a file containing pixel data in a recognized file format.

Returns:

an image which gets its pixel data from the specified file.

Throws:

SecurityException - if a security manager exists and its checkRead method doesn't allow the operation.

See Also:

getImage

public abstract Image getImage(URL url)

Returns an image which gets pixel data from the specified URL. The pixel data referenced by the specified URL must be in one of the following formats: GIF, JPEG or PNG. The underlying toolkit attempts to resolve multiple requests with the same URL to the same returned Image.

Since the mechanism required to facilitate this sharing of Image objects may continue to hold onto images that are no longer in use for an indefinite period of time, developers are encouraged to implement their own caching of images by using the createImage variant wherever available. If the image data stored at the specified URL changes, the Image object returned from this method may still contain stale information which was fetched from the URL after a prior call. Previously loaded image data can be manually discarded by calling the flush method on the returned Image.

This method first checks if there is a security manager installed. If so, the method calls the security manager's checkPermission method with the corresponding permission to ensure that the access to the image is allowed. If the connection to the specified URL requires either URLPermission or SocketPermission, then URLPermission is used for security checks.

Parameters:

url - the URL to use in fetching the pixel data.

Returns:

an image which gets its pixel data from the specified URL.

Throws:

SecurityException - if a security manager exists and its checkPermission method doesn't allow the operation.

See Also:

createImage

public abstract Image createImage(String filename)

Returns an image which gets pixel data from the specified file. The returned Image is a new object which will not be shared with any other caller of this method or its getImage variant.

This method first checks if there is a security manager installed. If so, the method calls the security manager's checkRead method with the specified file to ensure that the image creation is allowed.

Parameters:

filename - the name of a file containing pixel data in a recognized file format.

Returns:

an image which gets its pixel data from the specified file.

Throws:

SecurityException - if a security manager exists and its checkRead method doesn't allow the operation.

See Also:

createImage

public abstract Image createImage(URL url)

Returns an image which gets pixel data from the specified URL. The returned Image is a new object which will not be shared with any other caller of this method or its getImage variant.

This method first checks if there is a security manager installed. If so, the method calls the security manager's checkPermission method with the corresponding permission to ensure that the image creation is allowed. If the connection to the specified URL requires either URLPermission or SocketPermission, then URLPermission is used for security checks.

Parameters:

url - the URL to use in fetching the pixel data.

Returns:

an image which gets its pixel data from the specified URL.

Throws:

SecurityException - if a security manager exists and its checkPermission method doesn't allow the operation.

See Also:

prepareImage

public abstract boolean prepareImage(Image image, int width, int height, ImageObserver observer)

Prepares an image for rendering.

If the values of the width and height arguments are both -1, this method prepares the image for rendering on the default screen; otherwise, this method prepares an image for rendering on the default screen at the specified width and height.

The image data is downloaded asynchronously in another thread, and an appropriately scaled screen representation of the image is generated.

This method is called by components prepareImage methods.

Information on the flags returned by this method can be found with the definition of the ImageObserver interface.

Parameters:

image - the image for which to prepare a screen representation.

width - the width of the desired screen representation, or -1.

height - the height of the desired screen representation, or -1.

observer - the ImageObserver object to be notified as the image is being prepared.

Returns:

true if the image has already been fully prepared; false otherwise.

See Also:

checkImage

public abstract int checkImage(Image image, int width, int height, ImageObserver observer)

Indicates the construction status of a specified image that is being prepared for display.

If the values of the width and height arguments are both -1, this method returns the construction status of a screen representation of the specified image in this toolkit. Otherwise, this method returns the construction status of a scaled representation of the image at the specified width and height.

This method does not cause the image to begin loading. An application must call prepareImage to force the loading of an image.

This method is called by the component's checkImage methods.

Information on the flags returned by this method can be found with the definition of the ImageObserver interface.

Parameters:

image - the image whose status is being checked.

width - the width of the scaled version whose status is being checked, or -1.

height - the height of the scaled version whose status is being checked, or -1.

observer - the ImageObserver object to be notified as the image is being prepared.

Returns:

the bitwise inclusive OR of the ImageObserver flags for the image data that is currently available.

See Also:

createImage

public abstract Image createImage(ImageProducer producer)

Creates an image with the specified image producer.

Parameters:

producer - the image producer to be used.

Returns:

an image with the specified image producer.

See Also:

createImage

public Image createImage(byte[] imagedata)

Creates an image which decodes the image stored in the specified byte array.

The data must be in some image format, such as GIF or JPEG, that is supported by this toolkit.

Parameters:: imagedata - an array of bytes, representing image data in a supported image format.
Returns:: an image.
Since:: 1.1

createImage

public abstract Image createImage(byte[] imagedata, int imageoffset, int imagelength)

Creates an image which decodes the image stored in the specified byte array, and at the specified offset and length. The data must be in some image format, such as GIF or JPEG, that is supported by this toolkit.

Parameters:: imagedata - an array of bytes, representing image data in a supported image format.; imageoffset - the offset of the beginning of the data in the array.; imagelength - the length of the data in the array.
Returns:: an image.
Since:: 1.1

getPrintJob

public abstract PrintJob getPrintJob(Frame frame, String jobtitle, Properties props)

Gets a PrintJob object which is the result of initiating a print operation on the toolkit's platform.

Each actual implementation of this method should first check if there is a security manager installed. If there is, the method should call the security manager's checkPrintJobAccess method to ensure initiation of a print operation is allowed. If the default implementation of checkPrintJobAccess is used (that is, that method is not overridden), then this results in a call to the security manager's checkPermission method with a RuntimePermission("queuePrintJob") permission.

Parameters:

frame - the parent of the print dialog. May not be null.

jobtitle - the title of the PrintJob. A null title is equivalent to "".

props - a Properties object containing zero or more properties. Properties are not standardized and are not consistent across implementations. Because of this, PrintJobs which require job and page control should use the version of this function which takes JobAttributes and PageAttributes objects. This object may be updated to reflect the user's job choices on exit. May be null.

Returns:

a PrintJob object, or null if the user cancelled the print job.

Throws:

NullPointerException - if frame is null

SecurityException - if this thread is not allowed to initiate a print job request

Since:

1.1

See Also:

getPrintJob

public PrintJob getPrintJob(Frame frame, String jobtitle, JobAttributes jobAttributes, PageAttributes pageAttributes)

Gets a PrintJob object which is the result of initiating a print operation on the toolkit's platform.

Parameters:

frame - the parent of the print dialog. May not be null.

jobtitle - the title of the PrintJob. A null title is equivalent to "".

jobAttributes - a set of job attributes which will control the PrintJob. The attributes will be updated to reflect the user's choices as outlined in the JobAttributes documentation. May be null.

pageAttributes - a set of page attributes which will control the PrintJob. The attributes will be applied to every page in the job. The attributes will be updated to reflect the user's choices as outlined in the PageAttributes documentation. May be null.

Returns:

a PrintJob object, or null if the user cancelled the print job.

Throws:

NullPointerException - if frame is null

IllegalArgumentException - if pageAttributes specifies differing cross feed and feed resolutions. Also if this thread has access to the file system and jobAttributes specifies print to file, and the specified destination file exists but is a directory rather than a regular file, does not exist but cannot be created, or cannot be opened for any other reason. However in the case of print to file, if a dialog is also requested to be displayed then the user will be given an opportunity to select a file and proceed with printing. The dialog will ensure that the selected output file is valid before returning from this method.

SecurityException - if this thread is not allowed to initiate a print job request, or if jobAttributes specifies print to file, and this thread is not allowed to access the file system

Since:

1.3

See Also:

beep

public abstract void beep()

Emits an audio beep depending on native system settings and hardware capabilities.

Since:: 1.1

getSystemClipboard

public abstract Clipboard getSystemClipboard() throws HeadlessException

Gets the singleton instance of the system Clipboard which interfaces with clipboard facilities provided by the native platform. This clipboard enables data transfer between Java programs and native applications which use native clipboard facilities.

In addition to any and all default formats text returned by the system Clipboard's getTransferData() method is available in the following flavors:

DataFlavor.stringFlavor
DataFlavor.plainTextFlavor (deprecated)

As with java.awt.datatransfer.StringSelection, if the requested flavor is DataFlavor.plainTextFlavor, or an equivalent flavor, a Reader is returned. Note: The behavior of the system Clipboard's getTransferData() method for DataFlavor.plainTextFlavor, and equivalent DataFlavors, is inconsistent with the definition of DataFlavor.plainTextFlavor. Because of this, support for DataFlavor.plainTextFlavor, and equivalent flavors, is deprecated.

Each actual implementation of this method should first check if there is a security manager installed. If there is, the method should call the security manager's checkPermission method to check AWTPermission("accessClipboard").

Returns:

the system Clipboard

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

Since:

1.1

See Also:

getSystemSelection

public Clipboard getSystemSelection() throws HeadlessException

Gets the singleton instance of the system selection as a Clipboard object. This allows an application to read and modify the current, system-wide selection.

An application is responsible for updating the system selection whenever the user selects text, using either the mouse or the keyboard. Typically, this is implemented by installing a FocusListener on all Components which support text selection, and, between FOCUS_GAINED and FOCUS_LOST events delivered to that Component, updating the system selection Clipboard when the selection changes inside the Component. Properly updating the system selection ensures that a Java application will interact correctly with native applications and other Java applications running simultaneously on the system. Note that java.awt.TextComponent and javax.swing.text.JTextComponent already adhere to this policy. When using these classes, and their subclasses, developers need not write any additional code.

Some platforms do not support a system selection Clipboard. On those platforms, this method will return null. In such a case, an application is absolved from its responsibility to update the system selection Clipboard as described above.

Returns:

the system selection as a Clipboard, or null if the native platform does not support a system selection Clipboard

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

Since:

1.4

See Also:

getMenuShortcutKeyMask

@Deprecated(since="10") public int getMenuShortcutKeyMask() throws HeadlessException

Deprecated.

It is recommended that extended modifier keys and getMenuShortcutKeyMaskEx() be used instead

Determines which modifier key is the appropriate accelerator key for menu shortcuts.

Menu shortcuts, which are embodied in the MenuShortcut class, are handled by the MenuBar class.

By default, this method returns Event.CTRL_MASK. Toolkit implementations should override this method if the Control key isn't the correct key for accelerators.

Returns:

the modifier mask on the Event class that is used for menu shortcuts on this toolkit.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

Since:

1.1

See Also:

getMenuShortcutKeyMaskEx

public int getMenuShortcutKeyMaskEx() throws HeadlessException

Determines which extended modifier key is the appropriate accelerator key for menu shortcuts.

Menu shortcuts, which are embodied in the MenuShortcut class, are handled by the MenuBar class.

By default, this method returns InputEvent.CTRL_DOWN_MASK. Toolkit implementations should override this method if the Control key isn't the correct key for accelerators.

Returns:

the modifier mask on the InputEvent class that is used for menu shortcuts on this toolkit

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

Since:

See Also:

getLockingKeyState

public boolean getLockingKeyState(int keyCode) throws UnsupportedOperationException

Returns whether the given locking key on the keyboard is currently in its "on" state. Valid key codes are VK_CAPS_LOCK, VK_NUM_LOCK, VK_SCROLL_LOCK, and VK_KANA_LOCK.

Parameters:

keyCode - the key code

Returns:

true if the given key is currently in its "on" state; otherwise false

Throws:

IllegalArgumentException - if keyCode is not one of the valid key codes

UnsupportedOperationException - if the host system doesn't allow getting the state of this key programmatically, or if the keyboard doesn't have this key

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

Since:

1.3

See Also:

setLockingKeyState

public void setLockingKeyState(int keyCode, boolean on) throws UnsupportedOperationException

Sets the state of the given locking key on the keyboard. Valid key codes are VK_CAPS_LOCK, VK_NUM_LOCK, VK_SCROLL_LOCK, and VK_KANA_LOCK.

Depending on the platform, setting the state of a locking key may involve event processing and therefore may not be immediately observable through getLockingKeyState.

Parameters:

keyCode - the key code

on - the state of the key

Throws:

IllegalArgumentException - if keyCode is not one of the valid key codes

UnsupportedOperationException - if the host system doesn't allow setting the state of this key programmatically, or if the keyboard doesn't have this key

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

Since:

1.3

See Also:

getNativeContainer

protected static Container getNativeContainer(Component c)

Give native peers the ability to query the native container given a native component (eg the direct parent may be lightweight).

Parameters:: c - the component to fetch the container for
Returns:: the native container object for the component

createCustomCursor

public Cursor createCustomCursor(Image cursor, Point hotSpot, String name) throws IndexOutOfBoundsException, HeadlessException

Creates a new custom cursor object. If the image to display is invalid, the cursor will be hidden (made completely transparent), and the hotspot will be set to (0, 0).

Note that multi-frame images are invalid and may cause this method to hang.

Parameters:

cursor - the image to display when the cursor is activated

hotSpot - the X and Y of the large cursor's hot spot; the hotSpot values must be less than the Dimension returned by getBestCursorSize

name - a localized description of the cursor, for Java Accessibility use

Returns:

the cursor created

Throws:

IndexOutOfBoundsException - if the hotSpot values are outside the bounds of the cursor

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

Since:

1.2

See Also:

getBestCursorSize

public Dimension getBestCursorSize(int preferredWidth, int preferredHeight) throws HeadlessException

Returns the supported cursor dimension which is closest to the desired sizes. Systems which only support a single cursor size will return that size regardless of the desired sizes. Systems which don't support custom cursors will return a dimension of 0, 0.

Note: if an image is used whose dimensions don't match a supported size (as returned by this method), the Toolkit implementation will attempt to resize the image to a supported size. Since converting low-resolution images is difficult, no guarantees are made as to the quality of a cursor image which isn't a supported size. It is therefore recommended that this method be called and an appropriate image used so no image conversion is made.

Parameters:

preferredWidth - the preferred cursor width the component would like to use.

preferredHeight - the preferred cursor height the component would like to use.

Returns:

the closest matching supported cursor size, or a dimension of 0,0 if the Toolkit implementation doesn't support custom cursors.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

Since:

1.2

See Also:

getMaximumCursorColors

public int getMaximumCursorColors() throws HeadlessException

Returns the maximum number of colors the Toolkit supports in a custom cursor palette.

Note: if an image is used which has more colors in its palette than the supported maximum, the Toolkit implementation will attempt to flatten the palette to the maximum. Since converting low-resolution images is difficult, no guarantees are made as to the quality of a cursor image which has more colors than the system supports. It is therefore recommended that this method be called and an appropriate image used so no image conversion is made.

Returns:

the maximum number of colors, or zero if custom cursors are not supported by this Toolkit implementation.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

Since:

1.2

See Also:

isFrameStateSupported

public boolean isFrameStateSupported(int state) throws HeadlessException

Returns whether Toolkit supports this state for Frames. This method tells whether the UI concept of, say, maximization or iconification is supported. It will always return false for "compound" states like Frame.ICONIFIED|Frame.MAXIMIZED_VERT. In other words, the rule of thumb is that only queries with a single frame state constant as an argument are meaningful.

Note that supporting a given concept is a platform- dependent feature. Due to native limitations the Toolkit object may report a particular state as supported, however at the same time the Toolkit object will be unable to apply the state to a given frame. This circumstance has two following consequences:

Only the return value of false for the present method actually indicates that the given state is not supported. If the method returns true the given state may still be unsupported and/or unavailable for a particular frame.
The developer should consider examining the value of the WindowEvent.getNewState() method of the WindowEvent received through the WindowStateListener, rather than assuming that the state given to the setExtendedState() method will be definitely applied. For more information see the documentation for the Frame.setExtendedState(int) method.

Parameters:

state - one of named frame state constants.

Returns:

true is this frame state is supported by this Toolkit implementation, false otherwise.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true.

Since:

1.4

See Also:

getProperty

public static String getProperty(String key, String defaultValue)

Gets a property with the specified key and default. This method returns defaultValue if the property is not found.

Parameters:: key - the key; defaultValue - the default value
Returns:: the value of the property or the default value if the property was not found

getSystemEventQueue

public final EventQueue getSystemEventQueue()

Get the application's or applet's EventQueue instance. Depending on the Toolkit implementation, different EventQueues may be returned for different applets. Applets should therefore not assume that the EventQueue instance returned by this method will be shared by other applets or the system.

If there is a security manager then its checkPermission method is called to check AWTPermission("accessEventQueue").

Returns:

the EventQueue object

Throws:

SecurityException - if a security manager is set and it denies access to the EventQueue

See Also:

getSystemEventQueueImpl

protected abstract EventQueue getSystemEventQueueImpl()

Gets the application's or applet's EventQueue instance, without checking access. For security reasons, this can only be called from a Toolkit subclass.

Returns:: the EventQueue object

createDragGestureRecognizer

public <T extends DragGestureRecognizer> T createDragGestureRecognizer(Class<T> abstractRecognizerClass, DragSource ds, Component c, int srcActions, DragGestureListener dgl)

Creates a concrete, platform dependent, subclass of the abstract DragGestureRecognizer class requested, and associates it with the DragSource, Component and DragGestureListener specified. subclasses should override this to provide their own implementation

Type Parameters:

T - the type of DragGestureRecognizer to create

Parameters:

abstractRecognizerClass - The abstract class of the required recognizer

ds - The DragSource

c - The Component target for the DragGestureRecognizer

srcActions - The actions permitted for the gesture

dgl - The DragGestureListener

Returns:

the new object or null. Always returns null if GraphicsEnvironment.isHeadless() returns true.

See Also:

getDesktopProperty

public final Object getDesktopProperty(String propertyName)

Obtains a value for the specified desktop property. A desktop property is a uniquely named value for a resource that is Toolkit global in nature. Usually it also is an abstract representation for an underlying platform dependent desktop setting. For more information on desktop properties supported by the AWT see AWT Desktop Properties.

Parameters:: propertyName - the property name
Returns:: the value for the specified desktop property

setDesktopProperty

protected final void setDesktopProperty(String name, Object newValue)

Sets the named desktop property to the specified value and fires a property change event to notify any listeners that the value has changed.

Parameters:: name - the property name; newValue - the new property value

lazilyLoadDesktopProperty

protected Object lazilyLoadDesktopProperty(String name)

An opportunity to lazily evaluate desktop property values.

Parameters:: name - the name
Returns:: the desktop property or null

initializeDesktopProperties

protected void initializeDesktopProperties()

initializeDesktopProperties

addPropertyChangeListener

public void addPropertyChangeListener(String name, PropertyChangeListener pcl)

Adds the specified property change listener for the named desktop property. When a PropertyChangeListenerProxy object is added, its property name is ignored, and the wrapped listener is added. If name is null or pcl is null, no exception is thrown and no action is performed.

Parameters:

name - The name of the property to listen for

pcl - The property change listener

Since:

1.2

See Also:

removePropertyChangeListener

public void removePropertyChangeListener(String name, PropertyChangeListener pcl)

Removes the specified property change listener for the named desktop property. When a PropertyChangeListenerProxy object is removed, its property name is ignored, and the wrapped listener is removed. If name is null or pcl is null, no exception is thrown and no action is performed.

Parameters:

name - The name of the property to remove

pcl - The property change listener

Since:

1.2

See Also:

getPropertyChangeListeners

public PropertyChangeListener[] getPropertyChangeListeners()

Returns an array of all the property change listeners registered on this toolkit. The returned array contains PropertyChangeListenerProxy objects that associate listeners with the names of desktop properties.

Returns:

all of this toolkit's PropertyChangeListener objects wrapped in java.beans.PropertyChangeListenerProxy objects or an empty array if no listeners are added

Since:

1.4

See Also:

getPropertyChangeListeners

public PropertyChangeListener[] getPropertyChangeListeners(String propertyName)

Returns an array of all property change listeners associated with the specified name of a desktop property.

Parameters:

propertyName - the named property

Returns:

all of the PropertyChangeListener objects associated with the specified name of a desktop property or an empty array if no such listeners are added

Since:

1.4

See Also:

isAlwaysOnTopSupported

public boolean isAlwaysOnTopSupported()

Returns whether the always-on-top mode is supported by this toolkit. To detect whether the always-on-top mode is supported for a particular Window, use Window.isAlwaysOnTopSupported().

Returns:

true, if current toolkit supports the always-on-top mode, otherwise returns false

Since:

1.6

See Also:

isModalityTypeSupported

public abstract boolean isModalityTypeSupported(Dialog.ModalityType modalityType)

Returns whether the given modality type is supported by this toolkit. If a dialog with unsupported modality type is created, then Dialog.ModalityType.MODELESS is used instead.

Parameters:

modalityType - modality type to be checked for support by this toolkit

Returns:

true, if current toolkit supports given modality type, false otherwise

Since:

1.6

See Also:

isModalExclusionTypeSupported

public abstract boolean isModalExclusionTypeSupported(Dialog.ModalExclusionType modalExclusionType)

Returns whether the given modal exclusion type is supported by this toolkit. If an unsupported modal exclusion type property is set on a window, then Dialog.ModalExclusionType.NO_EXCLUDE is used instead.

Parameters:

modalExclusionType - modal exclusion type to be checked for support by this toolkit

Returns:

true, if current toolkit supports given modal exclusion type, false otherwise

Since:

1.6

See Also:

addAWTEventListener

public void addAWTEventListener(AWTEventListener listener, long eventMask)

Adds an AWTEventListener to receive all AWTEvents dispatched system-wide that conform to the given eventMask.

First, if there is a security manager, its checkPermission method is called with an AWTPermission("listenToAllAWTEvents") permission. This may result in a SecurityException.

eventMask is a bitmask of event types to receive. It is constructed by bitwise OR-ing together the event masks defined in AWTEvent.

Note: event listener use is not recommended for normal application use, but are intended solely to support special purpose facilities including support for accessibility, event record/playback, and diagnostic tracing. If listener is null, no exception is thrown and no action is performed.

Parameters:

listener - the event listener.

eventMask - the bitmask of event types to receive

Throws:

SecurityException - if a security manager exists and its checkPermission method doesn't allow the operation.

Since:

1.2

See Also:

removeAWTEventListener

public void removeAWTEventListener(AWTEventListener listener)

Removes an AWTEventListener from receiving dispatched AWTEvents.

First, if there is a security manager, its checkPermission method is called with an AWTPermission("listenToAllAWTEvents") permission. This may result in a SecurityException.

Parameters:

listener - the event listener.

Throws:

SecurityException - if a security manager exists and its checkPermission method doesn't allow the operation.

Since:

1.2

See Also:

getAWTEventListeners

public AWTEventListener[] getAWTEventListeners()

Returns an array of all the AWTEventListeners registered on this toolkit. If there is a security manager, its checkPermission method is called with an AWTPermission("listenToAllAWTEvents") permission. This may result in a SecurityException. Listeners can be returned within AWTEventListenerProxy objects, which also contain the event mask for the given listener. Note that listener objects added multiple times appear only once in the returned array.

Returns:

all of the AWTEventListeners or an empty array if no listeners are currently registered

Throws:

SecurityException - if a security manager exists and its checkPermission method doesn't allow the operation.

Since:

1.4

See Also:

getAWTEventListeners

public AWTEventListener[] getAWTEventListeners(long eventMask)

Returns an array of all the AWTEventListeners registered on this toolkit which listen to all of the event types specified in the eventMask argument. If there is a security manager, its checkPermission method is called with an AWTPermission("listenToAllAWTEvents") permission. This may result in a SecurityException. Listeners can be returned within AWTEventListenerProxy objects, which also contain the event mask for the given listener. Note that listener objects added multiple times appear only once in the returned array.

Parameters:

eventMask - the bitmask of event types to listen for

Returns:

all of the AWTEventListeners registered on this toolkit for the specified event types, or an empty array if no such listeners are currently registered

Throws:

SecurityException - if a security manager exists and its checkPermission method doesn't allow the operation.

Since:

1.4

See Also:

mapInputMethodHighlight

public abstract Map<TextAttribute,?> mapInputMethodHighlight(InputMethodHighlight highlight) throws HeadlessException

Returns a map of visual attributes for the abstract level description of the given input method highlight, or null if no mapping is found. The style field of the input method highlight is ignored. The map returned is unmodifiable.

Parameters:

highlight - input method highlight

Returns:

style attribute map, or null

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless returns true

Since:

1.3

See Also:

areExtraMouseButtonsEnabled

public boolean areExtraMouseButtonsEnabled() throws HeadlessException

Reports whether events from extra mouse buttons are allowed to be processed and posted into EventQueue.
To change the returned value it is necessary to set the sun.awt.enableExtraMouseButtons property before the Toolkit class initialization. This setting could be done on the application startup by the following command:

 java -Dsun.awt.enableExtraMouseButtons=false Application

Alternatively, the property could be set in the application by using the following code:

 System.setProperty("sun.awt.enableExtraMouseButtons", "true");

before the Toolkit class initialization. If not set by the time of the Toolkit class initialization, this property will be initialized with true. Changing this value after the Toolkit class initialization will have no effect.

Returns:

true if events from extra mouse buttons are allowed to be processed and posted; false otherwise

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true

Since:

1.7

See Also:

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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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