diff options
Diffstat (limited to 'libjava/java/awt/Image.java')
| -rw-r--r-- | libjava/java/awt/Image.java | 293 |
1 files changed, 143 insertions, 150 deletions
diff --git a/libjava/java/awt/Image.java b/libjava/java/awt/Image.java index fb9b404..d4b75b8 100644 --- a/libjava/java/awt/Image.java +++ b/libjava/java/awt/Image.java @@ -1,5 +1,5 @@ -/* Image.java -- Java class for images - Copyright (C) 1999 Free Software Foundation, Inc. +/* Image.java -- superclass for images + Copyright (C) 1999, 2002 Free Software Foundation, Inc. This file is part of GNU Classpath. @@ -38,160 +38,153 @@ exception statement from your version. */ package java.awt; -import java.awt.image.*; +import java.awt.image.AreaAveragingScaleFilter; +import java.awt.image.ImageObserver; +import java.awt.image.ImageProducer; +import java.awt.image.ReplicateScaleFilter; /** - * This is the abstract superclass of all image objects in Java. - * - * @author Aaron M. Renn (arenn@urbanophile.com) - */ -public abstract class Image -{ - -/* - * Static Variables + * This is the abstract superclass of all image objects in Java. + * + * @author Aaron M. Renn <arenn@urbanophile.com> + * @since 1.0 + * @status updated to 1.4 */ - -/** - * Constant indicating that the default scaling algorithm should be used. - */ -public static final int SCALE_DEFAULT = 1; - -/** - * Constant indicating that a fast scaling algorithm should be used. - */ -public static final int SCALE_FAST = 2; - -/** - * Constant indicating that a smooth scaling algorithm should be used. - */ -public static final int SCALE_SMOOTH = 4; - -/** - * Constant indicating that the <code>ReplicateScaleFilter</code> class - * algorithm should be used for scaling. - */ -public static final int SCALE_REPLICATE = 8; - -/** - * Constant indicating that the area averaging scaling algorithm should be - * used. - */ -public static final int SCALE_AREA_AVERAGING = 16; - -/** - * This variable is returned whenever a property that is not defined - * is requested. - */ -public static final Object UndefinedProperty = Image.class; - -/*************************************************************************/ - -/* - * Constructors - */ - -/** - * A default constructor for subclasses. - */ -public -Image() +public abstract class Image { -} - -/*************************************************************************/ - -/* - * Instance Methods - */ - -/** - * Returns the width of the image, or -1 if it is unknown. If the - * image width is unknown, the observer object will be notified when - * the value is known. - * - * @param observer The image observer for this object. - */ -public abstract int -getWidth(ImageObserver observer); - -/*************************************************************************/ - -/** - * Returns the height of the image, or -1 if it is unknown. If the - * image height is unknown, the observer object will be notified when - * the value is known. - * - * @param observer The image observer for this object. - */ -public abstract int -getHeight(ImageObserver observer); - -/*************************************************************************/ - -/** - * Returns the image producer object for this object. - * - * @return The image producer for this object. - */ -public abstract ImageProducer -getSource(); - -/*************************************************************************/ - -/** - * Returns a graphics context object for drawing an off-screen object. - * This method is only valid for off-screen objects. - * - * @return A graphics context object for an off-screen object. - */ -public abstract Graphics -getGraphics(); - -/*************************************************************************/ - -/** - * This method requests a named property for an object. The value of the - * property is returned. The value <code>UndefinedProperty</code> is - * returned if there is no property with the specified name. The value - * <code>null</code> is returned if the properties for the object are - * not yet known. In this case, the specified image observer is notified - * when the properties are known. - * - * @param name The requested property name. - * @param observer The image observer for this object. - */ -public abstract Object -getProperty(String name, ImageObserver observer); - -/*************************************************************************/ - -/** - * Scales the image to the requested dimension. - * - * XXX: FIXME - * - * @param width The width of the scaled image. - * @param height The height of the scaled image. - * @param flags A value indicating the algorithm to use, which will be - * set from contants defined in this class. - * - * @return The scaled <code>Image</code> object. - */ -public Image -getScaledInstance(int width, int height, int flags) + /** + * This variable is returned whenever a property that is not defined + * is requested. + */ + // For debug purposes, this might as well be a unique string. + public static final Object UndefinedProperty + = new String("undefined property"); + + /** + * Constant indicating that the default scaling algorithm should be used. + * + * @since 1.1 + */ + public static final int SCALE_DEFAULT = 1; + + /** + * Constant indicating that a fast scaling algorithm should be used. + * + * @since 1.1 + */ + public static final int SCALE_FAST = 2; + + /** + * Constant indicating that a smooth scaling algorithm should be used. + * + * @since 1.1 + */ + public static final int SCALE_SMOOTH = 4; + + /** + * Constant indicating that the <code>ReplicateScaleFilter</code> class + * algorithm should be used for scaling. + * + * @see ReplicateScaleFilter + * @since 1.1 + */ + public static final int SCALE_REPLICATE = 8; + + /** + * Constant indicating that the area averaging scaling algorithm should be + * used. + * + * @see AreaAveragingScaleFilter + * @since 1.1 + */ + public static final int SCALE_AREA_AVERAGING = 16; + + /** + * A default constructor for subclasses. + */ + public Image() { - return null; } -/*************************************************************************/ - -/** - * Flushes (that is, destroys) any resources used for this image. This - * includes the actual image data. - */ -public abstract void -flush(); + /** + * Returns the width of the image, or -1 if it is unknown. If the + * image width is unknown, the observer object will be notified when + * the value is known. + * + * @param observer the image observer for this object + * @return the width in pixels + * @see #getHeight(ImageObserver) + */ + public abstract int getWidth(ImageObserver observer); + + /** + * Returns the height of the image, or -1 if it is unknown. If the + * image height is unknown, the observer object will be notified when + * the value is known. + * + * @param observer the image observer for this object + * @return the height in pixels + * @see #getWidth(ImageObserver) + */ + public abstract int getHeight(ImageObserver observer); + + /** + * Returns the image producer object for this object. The producer is the + * object which generates pixels for this image. + * + * @return the image producer for this object + */ + public abstract ImageProducer getSource(); + + /** + * Returns a graphics context object for drawing an off-screen object. + * This method is only valid for off-screen objects. + * + * @return a graphics context object for an off-screen object + * @see Graphics#createImage(int, int) + */ + public abstract Graphics getGraphics(); + + /** + * This method requests a named property for an object. The value of the + * property is returned. The value <code>UndefinedProperty</code> is + * returned if there is no property with the specified name. The value + * <code>null</code> is returned if the properties for the object are + * not yet known. In this case, the specified image observer is notified + * when the properties are known. + * + * @param name the requested property name + * @param observer the image observer for this object + * @return the named property, if available + * @see #UndefinedProperty + */ + public abstract Object getProperty(String name, ImageObserver observer); + + /** + * Scales the image to the requested dimension. A new Image with asynchronous + * loading will be produced according to the hints of the algorithm + * requested. If either the width or height is non-positive, it is adjusted + * to preserve the original aspect ratio. + * + * @param width the width of the scaled image + * @param height the height of the scaled image + * @param flags a value indicating the algorithm to use + * @return the scaled <code>Image</code> object + * @see #SCALE_DEFAULT + * @see #SCALE_FAST + * @see #SCALE_SMOOTH + * @see #SCALE_REPLICATE + * @see #SCALE_AREA_AVERAGING + * @since 1.1 + */ + public Image getScaledInstance(int width, int height, int flags) + { + throw new Error("not implemented"); + } + /** + * Flushes (that is, destroys) any resources used for this image. This + * includes the actual image data. + */ + public abstract void flush(); } // class Image - |