Java in a Nutshell

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The java.awt.image Package
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21.8 java.awt.image.ImageObserver (JDK 1.0)

This interface defines a method and associated constants used by classes that want to receive information asynchronously about the status of an image. Many methods that query information about an image take an ImageObserver as an argument. If the specified information is not available when requested, it is passed to the ImageObserver when it becomes available. Component implements this interface, and components are the most commonly used image observers.

public abstract interface ImageObserver {
    // Constants
            public static final int ABORT;
            public static final int ALLBITS;
            public static final int ERROR;
            public static final int FRAMEBITS;
            public static final int HEIGHT;
            public static final int PROPERTIES;
            public static final int SOMEBITS;
            public static final int WIDTH;
    // Public Instance Methods
            public abstract boolean imageUpdate(Image img, int infoflags, int x, int y, int width, int height);
}

Implemented By:

Component

Passed To:

Component.checkImage(), Component.prepareImage(), ComponentPeer.checkImage(), ComponentPeer.prepareImage(), Graphics.drawImage(), Image.getHeight(), Image.getProperty(), Image.getWidth(), Toolkit.checkImage(), Toolkit.prepareImage()


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