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java.awt
abstract public class: GraphicsDevice [javadoc | source]
java.lang.Object
   java.awt.GraphicsDevice
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.

Nested Class Summary:
public static enum class  GraphicsDevice.WindowTranslucency  Kinds of translucency supported by the underlying system. 
Field Summary
public static final  int TYPE_RASTER_SCREEN    Device is a raster screen. 
public static final  int TYPE_PRINTER    Device is a printer. 
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. 
Constructor:
 protected GraphicsDevice() 
Method from java.awt.GraphicsDevice Summary:
getAvailableAcceleratedMemory,   getBestConfiguration,   getConfigurations,   getDefaultConfiguration,   getDisplayMode,   getDisplayModes,   getFullScreenWindow,   getIDstring,   getTranslucencyCapableGC,   getType,   isDisplayChangeSupported,   isFullScreenSupported,   isWindowOpacitySupported,   isWindowPerpixelTranslucencySupported,   isWindowShapingSupported,   isWindowTranslucencySupported,   setDisplayMode,   setFullScreenWindow
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from java.awt.GraphicsDevice Detail:
 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.
 public GraphicsConfiguration getBestConfiguration(GraphicsConfigTemplate gct) 
 abstract public GraphicsConfiguration[] getConfigurations()
    Returns all of the GraphicsConfiguration objects associated with this GraphicsDevice.
 abstract public GraphicsConfiguration getDefaultConfiguration()
    Returns the default GraphicsConfiguration associated with this GraphicsDevice.
 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.
 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.
 public Window getFullScreenWindow() 
    Returns the Window object representing the full-screen window if the device is in full-screen mode.
 abstract public 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 JavaTM 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".

 GraphicsConfiguration getTranslucencyCapableGC() 
 abstract public int getType()
    Returns the type of this GraphicsDevice.
 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 {@code true} and the application has already entered full-screen mode using #setFullScreenWindow ).
 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.
 static boolean isWindowOpacitySupported() 
    Returns whether the windowing system supports changing the opacity value of top-level windows. Note that this method may sometimes return true, but the native windowing system may still not support the concept of translucency (due to the bugs in the windowing system).
 boolean isWindowPerpixelTranslucencySupported() 
 static boolean isWindowShapingSupported() 
    Returns whether the windowing system supports changing the shape of top-level windows. Note that this method may sometimes return true, but the native windowing system may still not support the concept of shaping (due to the bugs in the windowing system).
 public boolean isWindowTranslucencySupported(WindowTranslucency translucencyKind) 
    Returns whether the given level of translucency is supported by this graphics device.
 public  void setDisplayMode(DisplayMode dm) 
    Sets the display mode of this graphics device. This is only allowed if #isDisplayChangeSupported() returns {@code true} and may require first entering full-screen exclusive mode using #setFullScreenWindow providing that full-screen exclusive mode is supported (i.e., #isFullScreenSupported() returns {@code 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);
    }
    
 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 {@code 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 {@code 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 {@code Frame} or {@code Dialog} object by using the {@code setUndecorated} method.

    When returning to windowed mode from an exclusive full-screen window, any display changes made by calling {@code setDisplayMode} are automatically restored to their original state.