java.awt.image

Class AbstractMultiResolutionImage

java.lang.Object

java.awt.Image

java.awt.image.AbstractMultiResolutionImage

All Implemented Interfaces:

MultiResolutionImage

Direct Known Subclasses:

BaseMultiResolutionImage

public abstract class AbstractMultiResolutionImage
extends Image
implements MultiResolutionImage

This class provides default implementations of several Image methods for classes that want to implement the interface. For example,

 
 public class CustomMultiResolutionImage extends AbstractMultiResolutionImage {

     final Image[] resolutionVariants;

     public CustomMultiResolutionImage(Image... resolutionVariants) {
          this.resolutionVariants = resolutionVariants;
     }

     public Image getResolutionVariant(
             double destImageWidth, double destImageHeight) {
         // return a resolution variant based on the given destination image size
     }

     public List<Image> getResolutionVariants() {
         return Collections.unmodifiableList(Arrays.asList(resolutionVariants));
     }

     protected Image getBaseImage() {
         return resolutionVariants[0];
     }
 }
  

Since:

1.9

See Also:

Image, MultiResolutionImage

Field Summary

Fields inherited from class java.awt.Image

accelerationPriority, SCALE_AREA_AVERAGING, SCALE_DEFAULT, SCALE_FAST, SCALE_REPLICATE, SCALE_SMOOTH, UndefinedProperty

Constructor Summary

Constructors

Constructor and Description
AbstractMultiResolutionImage()

Method Summary

Modifier and Type	Method and Description
protected abstract Image	getBaseImage() Return the base image representing the best version of the image for rendering at the default width and height.
Graphics	getGraphics() Creates a graphics context for drawing to an off-screen image.
int	getHeight(ImageObserver observer) Determines the height of the image.
Object	getProperty(String name, ImageObserver observer) Gets a property of this image by name.
ImageProducer	getSource() Gets the object that produces the pixels for the image.
int	getWidth(ImageObserver observer) Determines the width of the image.

Methods inherited from class java.awt.Image

flush, getAccelerationPriority, getCapabilities, getScaledInstance, setAccelerationPriority

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.awt.image.MultiResolutionImage

getResolutionVariant, getResolutionVariants

Constructor Detail

AbstractMultiResolutionImage

public AbstractMultiResolutionImage()

Method Detail

getWidth

public int getWidth(ImageObserver observer)

Description copied from class: Image

Determines the width of the image. If the width is not yet known, this method returns -1 and the specified ImageObserver object is notified later.

Specified by:

getWidth in class Image

Parameters:

observer - an object waiting for the image to be loaded.

Returns:

the width of this image, or -1 if the width is not yet known.

See Also:

Image.getHeight(java.awt.image.ImageObserver), ImageObserver

getHeight

public int getHeight(ImageObserver observer)

Description copied from class: Image

Determines the height of the image. If the height is not yet known, this method returns -1 and the specified ImageObserver object is notified later.

Specified by:

getHeight in class Image

Parameters:

observer - an object waiting for the image to be loaded.

Returns:

the height of this image, or -1 if the height is not yet known.

See Also:

Image.getWidth(java.awt.image.ImageObserver), ImageObserver

getSource

public ImageProducer getSource()

Description copied from class: Image

Gets the object that produces the pixels for the image. This method is called by the image filtering classes and by methods that perform image conversion and scaling.

Specified by:

getSource in class Image

Returns:

the image producer that produces the pixels for this image.

See Also:

ImageProducer

getGraphics

public Graphics getGraphics()

Description copied from class: Image

Creates a graphics context for drawing to an off-screen image. This method can only be called for off-screen images.

Specified by:

getGraphics in class Image

Returns:

a graphics context to draw to the off-screen image.

See Also:

Graphics, Component.createImage(int, int)

getProperty

public Object getProperty(String name,
                          ImageObserver observer)

Description copied from class: Image

Gets a property of this image by name.

Individual property names are defined by the various image formats. If a property is not defined for a particular image, this method returns the UndefinedProperty object.

If the properties for this image are not yet known, this method returns null, and the ImageObserver object is notified later.

The property name "comment" should be used to store an optional comment which can be presented to the application as a description of the image, its source, or its author.

Specified by:

getProperty in class Image

Parameters:

name - a property name.

observer - an object waiting for this image to be loaded.

Returns:

the value of the named property.

See Also:

ImageObserver, Image.UndefinedProperty

getBaseImage

protected abstract Image getBaseImage()

Return the base image representing the best version of the image for rendering at the default width and height.

Returns:

the base image of the set of multi-resolution images

Since:

1.9