Class GraphicsDevice
- java.lang.Object
-
- java.awt.GraphicsDevice
public abstract class GraphicsDevice extends Object
The GraphicsDevice
class describes the graphics devices that might be available in a particular graphics environment. These include screen and printer devices. Note that there can be many screens and many printers in an instance of GraphicsEnvironment
. Each graphics device has one or more GraphicsConfiguration
objects associated with it. These objects specify the different configurations in which the GraphicsDevice
can be used.
In a multi-screen environment, the GraphicsConfiguration
objects can be used to render components on multiple screens. The following code sample demonstrates how to create a JFrame
object for each GraphicsConfiguration
on each screen device in the GraphicsEnvironment
:
GraphicsEnvironment ge = GraphicsEnvironment. getLocalGraphicsEnvironment(); GraphicsDevice[] gs = ge.getScreenDevices(); for (int j = 0; j < gs.length; j++) { GraphicsDevice gd = gs[j]; GraphicsConfiguration[] gc = gd.getConfigurations(); for (int i=0; i < gc.length; i++) { JFrame f = new JFrame(gs[j].getDefaultConfiguration()); Canvas c = new Canvas(gc[i]); Rectangle gcBounds = gc[i].getBounds(); int xoffs = gcBounds.x; int yoffs = gcBounds.y; f.getContentPane().add(c); f.setLocation((i*50)+xoffs, (i*60)+yoffs); f.show(); } }
For more information on full-screen exclusive mode API, see the Full-Screen Exclusive Mode API Tutorial.
- See Also:
-
GraphicsEnvironment
,GraphicsConfiguration
Nested Class Summary
Modifier and Type | Class | Description |
---|---|---|
static class | GraphicsDevice.WindowTranslucency | Kinds of translucency supported by the underlying system. |
Field Summary
Modifier and Type | Field | Description |
---|---|---|
static int | TYPE_IMAGE_BUFFER | Device is an image buffer. |
static int | TYPE_PRINTER | Device is a printer. |
static int | TYPE_RASTER_SCREEN | Device is a raster screen. |
Constructor Summary
Modifier | Constructor | Description |
---|---|---|
protected | GraphicsDevice() | This is an abstract class that cannot be instantiated directly. |
Method Summary
Modifier and Type | Method | Description |
---|---|---|
int | getAvailableAcceleratedMemory() | This method returns the number of bytes available in accelerated memory on this device. |
GraphicsConfiguration | getBestConfiguration(GraphicsConfigTemplate gct) | Returns the "best" configuration possible that passes the criteria defined in the |
abstract GraphicsConfiguration[] | getConfigurations() | Returns all of the |
abstract GraphicsConfiguration | getDefaultConfiguration() | Returns the default |
DisplayMode | getDisplayMode() | Returns the current display mode of this |
DisplayMode[] | getDisplayModes() | Returns all display modes available for this |
Window | getFullScreenWindow() | Returns the |
abstract String | getIDstring() | Returns the identification string associated with this |
abstract int | getType() | Returns the type of this |
boolean | isDisplayChangeSupported() | Returns |
boolean | isFullScreenSupported() | Returns |
boolean | isWindowTranslucencySupported(GraphicsDevice.WindowTranslucency translucencyKind) | Returns whether the given level of translucency is supported by this graphics device. |
void | setDisplayMode(DisplayMode dm) | Sets the display mode of this graphics device. |
void | setFullScreenWindow(Window w) | Enter full-screen mode, or return to windowed mode. |
Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Field Detail
TYPE_RASTER_SCREEN
public static final int TYPE_RASTER_SCREEN
Device is a raster screen.
- See Also:
- Constant Field Values
TYPE_PRINTER
public static final int TYPE_PRINTER
Device is a printer.
- See Also:
- Constant Field Values
TYPE_IMAGE_BUFFER
public static final int TYPE_IMAGE_BUFFER
Device is an image buffer. This buffer can reside in device or system memory but it is not physically viewable by the user.
- See Also:
- Constant Field Values
Constructor Detail
GraphicsDevice
protected GraphicsDevice()
This is an abstract class that cannot be instantiated directly. Instances must be obtained from a suitable factory or query method.
Method Detail
getType
public abstract int getType()
Returns the type of this GraphicsDevice
.
- Returns:
- the type of this
GraphicsDevice
, which can either be TYPE_RASTER_SCREEN, TYPE_PRINTER or TYPE_IMAGE_BUFFER. - See Also:
-
TYPE_RASTER_SCREEN
,TYPE_PRINTER
,TYPE_IMAGE_BUFFER
getIDstring
public abstract String getIDstring()
Returns the identification string associated with this GraphicsDevice
.
A particular program might use more than one GraphicsDevice
in a GraphicsEnvironment
. This method returns a String
identifying a particular GraphicsDevice
in the local GraphicsEnvironment
. Although there is no public method to set this String
, a programmer can use the String
for debugging purposes. Vendors of the Java™ Runtime Environment can format the return value of the String
. To determine how to interpret the value of the String
, contact the vendor of your Java Runtime. To find out who the vendor is, from your program, call the getProperty
method of the System class with "java.vendor".
- Returns:
- a
String
that is the identification of thisGraphicsDevice
.
getConfigurations
public abstract GraphicsConfiguration[] getConfigurations()
Returns all of the GraphicsConfiguration
objects associated with this GraphicsDevice
.
- Returns:
- an array of
GraphicsConfiguration
objects that are associated with thisGraphicsDevice
.
getDefaultConfiguration
public abstract GraphicsConfiguration getDefaultConfiguration()
Returns the default GraphicsConfiguration
associated with this GraphicsDevice
.
- Returns:
- the default
GraphicsConfiguration
of thisGraphicsDevice
.
getBestConfiguration
public GraphicsConfiguration getBestConfiguration(GraphicsConfigTemplate gct)
Returns the "best" configuration possible that passes the criteria defined in the GraphicsConfigTemplate
.
- Parameters:
-
gct
- theGraphicsConfigTemplate
object used to obtain a validGraphicsConfiguration
- Returns:
- a
GraphicsConfiguration
that passes the criteria defined in the specifiedGraphicsConfigTemplate
. - See Also:
GraphicsConfigTemplate
isFullScreenSupported
public boolean isFullScreenSupported()
Returns true
if this GraphicsDevice
supports full-screen exclusive mode. If a SecurityManager is installed, its checkPermission
method will be called with AWTPermission("fullScreenExclusive")
. isFullScreenSupported
returns true only if that permission is granted.
- Returns:
- whether full-screen exclusive mode is available for this graphics device
- Since:
- 1.4
- See Also:
AWTPermission
setFullScreenWindow
public void setFullScreenWindow(Window w)
Enter full-screen mode, or return to windowed mode. The entered full-screen mode may be either exclusive or simulated. Exclusive mode is only available if isFullScreenSupported
returns true
.
Exclusive mode implies:
- Windows cannot overlap the full-screen window. All other application windows will always appear beneath the full-screen window in the Z-order.
- There can be only one full-screen window on a device at any time, so calling this method while there is an existing full-screen Window will cause the existing full-screen window to return to windowed mode.
- Input method windows are disabled. It is advisable to call
Component.enableInputMethods(false)
to make a component a non-client of the input method framework.
The simulated full-screen mode places and resizes the window to the maximum possible visible area of the screen. However, the native windowing system may modify the requested geometry-related data, so that the Window
object is placed and sized in a way that corresponds closely to the desktop settings.
When entering full-screen mode, if the window to be used as a full-screen window is not visible, this method will make it visible. It will remain visible when returning to windowed mode.
When entering full-screen mode, all the translucency effects are reset for the window. Its shape is set to null
, the opacity value is set to 1.0f, and the background color alpha is set to 255 (completely opaque). These values are not restored when returning to windowed mode.
It is unspecified and platform-dependent how decorated windows operate in full-screen mode. For this reason, it is recommended to turn off the decorations in a Frame
or Dialog
object by using the setUndecorated
method.
When returning to windowed mode from an exclusive full-screen window, any display changes made by calling setDisplayMode
are automatically restored to their original state.
- Parameters:
-
w
- a window to use as the full-screen window;null
if returning to windowed mode. Some platforms expect the fullscreen window to be a top-level component (i.e., aFrame
); therefore it is preferable to use aFrame
here rather than aWindow
. - Since:
- 1.4
- See Also:
-
isFullScreenSupported()
,getFullScreenWindow()
,setDisplayMode(java.awt.DisplayMode)
,Component.enableInputMethods(boolean)
,Component.setVisible(boolean)
,Frame.setUndecorated(boolean)
,Dialog.setUndecorated(boolean)
getFullScreenWindow
public Window getFullScreenWindow()
Returns the Window
object representing the full-screen window if the device is in full-screen mode.
- Returns:
- the full-screen window, or
null
if the device is not in full-screen mode. - Since:
- 1.4
- See Also:
setFullScreenWindow(Window)
isDisplayChangeSupported
public boolean isDisplayChangeSupported()
Returns true
if this GraphicsDevice
supports low-level display changes. On some platforms low-level display changes may only be allowed in full-screen exclusive mode (i.e., if isFullScreenSupported()
returns true
and the application has already entered full-screen mode using setFullScreenWindow(java.awt.Window)
).
- Returns:
- whether low-level display changes are supported for this graphics device.
- Since:
- 1.4
- See Also:
-
isFullScreenSupported()
,setDisplayMode(java.awt.DisplayMode)
,setFullScreenWindow(java.awt.Window)
setDisplayMode
public void setDisplayMode(DisplayMode dm)
Sets the display mode of this graphics device. This is only allowed if isDisplayChangeSupported()
returns true
and may require first entering full-screen exclusive mode using setFullScreenWindow(java.awt.Window)
providing that full-screen exclusive mode is supported (i.e., isFullScreenSupported()
returns true
).
The display mode must be one of the display modes returned by getDisplayModes()
, with one exception: passing a display mode with DisplayMode.REFRESH_RATE_UNKNOWN
refresh rate will result in selecting a display mode from the list of available display modes with matching width, height and bit depth. However, passing a display mode with DisplayMode.BIT_DEPTH_MULTI
for bit depth is only allowed if such mode exists in the list returned by getDisplayModes()
.
Example code:
Frame frame; DisplayMode newDisplayMode; GraphicsDevice gd; // create a Frame, select desired DisplayMode from the list of modes // returned by gd.getDisplayModes() ... if (gd.isFullScreenSupported()) { gd.setFullScreenWindow(frame); } else { // proceed in non-full-screen mode frame.setSize(...); frame.setLocation(...); frame.setVisible(true); } if (gd.isDisplayChangeSupported()) { gd.setDisplayMode(newDisplayMode); }
- Parameters:
-
dm
- The new display mode of this graphics device. - Throws:
-
IllegalArgumentException
- if theDisplayMode
supplied isnull
, or is not available in the array returned bygetDisplayModes
-
UnsupportedOperationException
- ifisDisplayChangeSupported
returnsfalse
- Since:
- 1.4
- See Also:
-
getDisplayMode()
,getDisplayModes()
,isDisplayChangeSupported()
getDisplayMode
public DisplayMode getDisplayMode()
Returns the current display mode of this GraphicsDevice
. The returned display mode is allowed to have a refresh rate DisplayMode.REFRESH_RATE_UNKNOWN
if it is indeterminate. Likewise, the returned display mode is allowed to have a bit depth DisplayMode.BIT_DEPTH_MULTI
if it is indeterminate or if multiple bit depths are supported.
- Returns:
- the current display mode of this graphics device.
- Since:
- 1.4
- See Also:
setDisplayMode(DisplayMode)
getDisplayModes
public DisplayMode[] getDisplayModes()
Returns all display modes available for this GraphicsDevice
. The returned display modes are allowed to have a refresh rate DisplayMode.REFRESH_RATE_UNKNOWN
if it is indeterminate. Likewise, the returned display modes are allowed to have a bit depth DisplayMode.BIT_DEPTH_MULTI
if it is indeterminate or if multiple bit depths are supported.
- Returns:
- all of the display modes available for this graphics device.
- Since:
- 1.4
getAvailableAcceleratedMemory
public int getAvailableAcceleratedMemory()
This method returns the number of bytes available in accelerated memory on this device. Some images are created or cached in accelerated memory on a first-come, first-served basis. On some operating systems, this memory is a finite resource. Calling this method and scheduling the creation and flushing of images carefully may enable applications to make the most efficient use of that finite resource.
Note that the number returned is a snapshot of how much memory is available; some images may still have problems being allocated into that memory. For example, depending on operating system, driver, memory configuration, and thread situations, the full extent of the size reported may not be available for a given image. There are further inquiry methods on the ImageCapabilities
object associated with a VolatileImage that can be used to determine whether a particular VolatileImage has been created in accelerated memory.
- Returns:
- number of bytes available in accelerated memory. A negative return value indicates that the amount of accelerated memory on this GraphicsDevice is indeterminate.
- Since:
- 1.4
- See Also:
-
Image.flush()
,ImageCapabilities.isAccelerated()
isWindowTranslucencySupported
public boolean isWindowTranslucencySupported(GraphicsDevice.WindowTranslucency translucencyKind)
Returns whether the given level of translucency is supported by this graphics device.
- Parameters:
-
translucencyKind
- a kind of translucency support - Returns:
- whether the given translucency kind is supported
- Since:
- 1.7