Module java.desktop

Package 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 MultiResolutionImage 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:

9

See Also:

• Image
• MultiResolutionImage

Field Summary

Fields declared in class java.awt.Image

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

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	AbstractMultiResolutionImage()	Constructor for subclasses to call.

Method Summary

Modifier and Type	Method	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()	As per the contract of the base Image#getGraphics() method, this implementation will always throw UnsupportedOperationException since only off-screen images can return a Graphics object.
int	getHeight(ImageObserver observer)	This method simply delegates to the same method on the base image and it is equivalent to: getBaseImage().getHeight(observer).
Object	getProperty(String name, ImageObserver observer)	This method simply delegates to the same method on the base image and it is equivalent to: getBaseImage().getProperty(name, observer).
ImageProducer	getSource()	This method simply delegates to the same method on the base image and it is equivalent to: getBaseImage().getSource().
int	getWidth(ImageObserver observer)	This method simply delegates to the same method on the base image and it is equivalent to: getBaseImage().getWidth(observer).

Methods declared in class java.awt.Image

flush, getAccelerationPriority, getCapabilities, getScaledInstance, setAccelerationPriority

Methods declared in class java.lang.Object

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

Methods declared in interface java.awt.image.MultiResolutionImage

getResolutionVariant, getResolutionVariants

Constructor Details

AbstractMultiResolutionImage

protected AbstractMultiResolutionImage()

Constructor for subclasses to call.

Method Details

getWidth

public int getWidth(ImageObserver observer)

This method simply delegates to the same method on the base image and it is equivalent to: getBaseImage().getWidth(observer).

Specified by:

getWidth in class Image

Parameters:

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

Returns:

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

Since:

9

See Also:

• getBaseImage()

getHeight

public int getHeight(ImageObserver observer)

This method simply delegates to the same method on the base image and it is equivalent to: getBaseImage().getHeight(observer).

Specified by:

getHeight in class Image

Parameters:

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

Returns:

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

Since:

9

See Also:

• getBaseImage()

getSource

public ImageProducer getSource()

This method simply delegates to the same method on the base image and it is equivalent to: getBaseImage().getSource().

Specified by:

getSource in class Image

Returns:

the image producer that produces the pixels for the base image

Since:

9

See Also:

• getBaseImage()

getGraphics

public Graphics getGraphics()

As per the contract of the base Image#getGraphics() method, this implementation will always throw UnsupportedOperationException since only off-screen images can return a Graphics object.

Specified by:

getGraphics in class Image

Returns:

throws UnsupportedOperationException

Throws:

UnsupportedOperationException - this method is not supported

See Also:

• Graphics
• Component.createImage(int, int)

getProperty

public Object getProperty(String name,
 ImageObserver observer)

This method simply delegates to the same method on the base image and it is equivalent to: getBaseImage().getProperty(name, observer).

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 in the base image

Since:

9

See Also:

• getBaseImage()

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:

9