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*
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* accompanied this code).
*
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package java.awt;
/**
* Capabilities and properties of buffers.
*
* @see java.awt.image.BufferStrategy#getCapabilities()
* @see GraphicsConfiguration#getBufferCapabilities
* @author Michael Martak
* @since 1.4
*/
public class BufferCapabilities implements Cloneable {
private ImageCapabilities frontCaps;
private ImageCapabilities backCaps;
private FlipContents flipContents;
/**
* Creates a new object for specifying buffering capabilities
* @param frontCaps the capabilities of the front buffer; cannot be
* {@code null}
* @param backCaps the capabilities of the back and intermediate buffers;
* cannot be {@code null}
* @param flipContents the contents of the back buffer after page-flipping,
* {@code null} if page flipping is not used (implies blitting)
* @exception IllegalArgumentException if frontCaps or backCaps are
* {@code null}
*/
public BufferCapabilities(ImageCapabilities frontCaps,
ImageCapabilities backCaps, FlipContents flipContents) {
if (frontCaps == null || backCaps == null) {
throw new IllegalArgumentException(
"Image capabilities specified cannot be null");
}
this.frontCaps = frontCaps;
this.backCaps = backCaps;
this.flipContents = flipContents;
}
/**
* @return the image capabilities of the front (displayed) buffer
*/
public ImageCapabilities getFrontBufferCapabilities() {
return frontCaps;
}
/**
* @return the image capabilities of all back buffers (intermediate buffers
* are considered back buffers)
*/
public ImageCapabilities getBackBufferCapabilities() {
return backCaps;
}
/**
* @return whether or not the buffer strategy uses page flipping; a set of
* buffers that uses page flipping
* can swap the contents internally between the front buffer and one or
* more back buffers by switching the video pointer (or by copying memory
* internally). A non-flipping set of
* buffers uses blitting to copy the contents from one buffer to
* another; when this is the case, {@code getFlipContents} returns
* {@code null}
*/
public boolean isPageFlipping() {
return (getFlipContents() != null);
}
/**
* @return the resulting contents of the back buffer after page-flipping.
* This value is {@code null} when the {@code isPageFlipping}
* returns {@code false}, implying blitting. It can be one of
* {@code FlipContents.UNDEFINED}
* (the assumed default), {@code FlipContents.BACKGROUND},
* {@code FlipContents.PRIOR}, or
* {@code FlipContents.COPIED}.
* @see #isPageFlipping
* @see FlipContents#UNDEFINED
* @see FlipContents#BACKGROUND
* @see FlipContents#PRIOR
* @see FlipContents#COPIED
*/
public FlipContents getFlipContents() {
return flipContents;
}
/**
* @return whether page flipping is only available in full-screen mode. If this
* is {@code true}, full-screen exclusive mode is required for
* page-flipping.
* @see #isPageFlipping
* @see GraphicsDevice#setFullScreenWindow
*/
public boolean isFullScreenRequired() {
return false;
}
/**
* @return whether or not
* page flipping can be performed using more than two buffers (one or more
* intermediate buffers as well as the front and back buffer).
* @see #isPageFlipping
*/
public boolean isMultiBufferAvailable() {
return false;
}
/**
* @return a copy of this BufferCapabilities object.
*/
public Object clone() {
try {
return super.clone();
} catch (CloneNotSupportedException e) {
// Since we implement Cloneable, this should never happen
throw new InternalError(e);
}
}
// Inner class FlipContents
/**
* A type-safe enumeration of the possible back buffer contents after
* page-flipping
* @since 1.4
*/
public static final class FlipContents extends AttributeValue {
private static int I_UNDEFINED = 0;
private static int I_BACKGROUND = 1;
private static int I_PRIOR = 2;
private static int I_COPIED = 3;
private static final String[] NAMES =
{ "undefined", "background", "prior", "copied" };
/**
* When flip contents are {@code UNDEFINED}, the
* contents of the back buffer are undefined after flipping.
* @see #isPageFlipping
* @see #getFlipContents
* @see #BACKGROUND
* @see #PRIOR
* @see #COPIED
*/
public static final FlipContents UNDEFINED =
new FlipContents(I_UNDEFINED);
/**
* When flip contents are {@code BACKGROUND}, the
* contents of the back buffer are cleared with the background color after
* flipping.
* @see #isPageFlipping
* @see #getFlipContents
* @see #UNDEFINED
* @see #PRIOR
* @see #COPIED
*/
public static final FlipContents BACKGROUND =
new FlipContents(I_BACKGROUND);
/**
* When flip contents are {@code PRIOR}, the
* contents of the back buffer are the prior contents of the front buffer
* (a true page flip).
* @see #isPageFlipping
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