javax.media.jai
Class NullCRIF

java.lang.Object
  extended byjavax.media.jai.CRIFImpl
      extended byjavax.media.jai.NullCRIF
All Implemented Interfaces:
ContextualRenderedImageFactory, RenderedImageFactory

public class NullCRIF
extends CRIFImpl

A ContextualRenderedImageFactory representing an operation which performs no processing of its image source(s) per se, i.e., a no-op.

The primary use of this image factory is as a utility class in implementing operations which generate only non-image data via the use of PropertyGenerators. A PropertyGenerator is defined as always contributing to the property environment of a given operation when it is returned by the getPropertyGenerators() method of the OperationDescriptor corresponding to the operation.

The procedure to be followed to register an operation which generates only non-image data as JAI image properties is as follows:

The properties emitted by the associated PropertyGenerator(s) will then be available by invoking getProperty() on the node returned by JAI.create() using the registered operation name.

Since:
JAI 1.1
See Also:
CRIFImpl, ContextualRenderedImageFactory

Field Summary
 
Fields inherited from class javax.media.jai.CRIFImpl
operationName
 
Constructor Summary
NullCRIF()
          Constructs a NullCRIF.
 
Method Summary
 RenderedImage create(ParameterBlock args, RenderingHints renderHints)
          Returns the first source in the source list in the ParameterBlock or the value returned by getSourcelessImage() if there are no soures.
static RenderedImage getSourcelessImage()
          Gets the value of the RenderedImage to be returned by the RIF.create() method when there are no sources in the ParameterBlock.
static void setSourcelessImage(RenderedImage im)
          Sets the value of the RenderedImage to be returned by the RenderedImageFactory.create() method when there are no sources in the ParameterBlock.
 
Methods inherited from class javax.media.jai.CRIFImpl
create, getBounds2D, getProperty, getPropertyNames, isDynamic, mapRenderContext
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

NullCRIF

public NullCRIF()
Constructs a NullCRIF. The operationName in the superclass is set to null.

Method Detail

setSourcelessImage

public static final void setSourcelessImage(RenderedImage im)
Sets the value of the RenderedImage to be returned by the RenderedImageFactory.create() method when there are no sources in the ParameterBlock.


getSourcelessImage

public static final RenderedImage getSourcelessImage()
Gets the value of the RenderedImage to be returned by the RIF.create() method when there are no sources in the ParameterBlock.

Returns:
a RenderedImage or null.

create

public RenderedImage create(ParameterBlock args,
                            RenderingHints renderHints)
Returns the first source in the source list in the ParameterBlock or the value returned by getSourcelessImage() if there are no soures.

Specified by:
create in interface RenderedImageFactory
Specified by:
create in class CRIFImpl
Throws:
ClassCastException - if there are sources and the source at index zero is not a RenderedImage.