java.awt
Class GraphicsEnvironment
java.lang.Object
|
+--java.awt.GraphicsEnvironment
public abstract class
GraphicsEnvironmentextends
Object This descibes the collection of GraphicsDevice and Font objects available
on a given platform. The resources might be local or remote, and specify
the valid configurations for displaying graphics.
Since:Author:- Eric Blake <ebb9@email.byu.edu>
See Also:
GraphicsEnvironment
protected GraphicsEnvironment()
The environment must be obtained from a factory or query method, hence
this constructor is protected.
createGraphics
public Graphics2D createGraphics(java.awt.image.BufferedImage image)
Return a Graphics2D object which will render into the specified image.
Parameters:
Returns:
- the object that renders into the image
getAllFonts
public Font[] getAllFonts()
Returns an array of the one-point size fonts available in this
environment. From there, the user can select the font and derive the
correct one of proper size and attributes, using deriveFont
.
Only one master version of each font appears in this array; if a font
can be derived from another, it must be created in that way.
Since:Returns:
- the array of available fonts
See Also:
getAvailableFontFamilyNames
public String[] getAvailableFontFamilyNames()
Returns an array of the font family names available in this environment.
This allows flexibility in choosing the style of font, while still letting
the Font class decide its best match.
Since:Returns:
- the array of available font families
See Also:
getAvailableFontFamilyNames
public String[] getAvailableFontFamilyNames(java.util.Locale l)
Returns an array of the font family names available in this environment,
localized to the current Locale if l is non-null. This allows
flexibility in choosing the style of font, while still letting the Font
class decide its best match.
Since:Parameters:
Returns:
- the array of available font families, localized
See Also:
getCenterPoint
public Point getCenterPoint()
Returns the point where a window should be centered. You should probably
also check that the window fits within the screen bounds. The default
simply returns the center of the maximum window bounds; subclasses should
override this if native objects (like scrollbars) make that off-centered.
Since:Returns:
Throws:
See Also:
getDefaultScreenDevice
public GraphicsDevice getDefaultScreenDevice()
Get the default screen GraphicsDevice object.
Returns:
- the default screen device
Throws:
getLocalGraphicsEnvironment
public static GraphicsEnvironment getLocalGraphicsEnvironment()
Returns the local graphics environment.
XXX Not implemented in Classpath yet.
Returns:
getMaximumWindowBounds
public Rectangle getMaximumWindowBounds()
Returns the maximum bounds for a centered window object. The default
implementation simply returns the bounds of the default configuration
of the default screen; subclasses should override this to if native
objects (like scrollbars) reduce what is truly available. Also,
subclasses should override this if the window should be centered across
a multi-screen display.
Since:Returns:
- the maximum window bounds
Throws:
See Also:
getScreenDevices
public GraphicsDevice[] getScreenDevices()
Get an array of all the GraphicsDevice objects.
Returns:
- the available graphics devices, may be 0 length
Throws:
isHeadless
public static boolean isHeadless()
Check if the local environment is headless, meaning that it does not
support a display, keyboard, or mouse. Many methods in the Abstract
Windows Toolkit (java.awt) throw a HeadlessException if this
returns true.
XXX For now, Classpath assumes that it is never headless.
Since:Returns:
- true if the environment is headless, meaning that graphics are
unsupported
isHeadlessInstance
public boolean isHeadlessInstance()
Check if the given environment is headless, meaning that it does not
support a display, keyboard, or mouse. Many methods in the Abstract
Windows Toolkit (java.awt) throw a HeadlessException if this
returns true. This default implementation returns false, so subclasses
need only override it if they are headless.
Since:Returns:
- true if the environment is headless, meaning that graphics are
unsupported