com.flagstone.transform.util.image
Class ImageFactory

java.lang.Object
  com.flagstone.transform.util.image.ImageFactory

public final class ImageFactory
extends Object

ImageFactory is used to generate an image definition object from an image stored in a file, references by a URL or read from an stream. An plug-in architecture allows decoders to be registered to handle different image formats. The ImageFactory provides a standard interface for using the decoders.

Currently PNG, BMP and JPEG encoded images are supported by dedicated decoders. The BufferedImageDecoder can be used to decode any format supported using Java's ImageIO, including PNG, BMP and JPG format images. New decoders can be added by implementing the ImageDecoder interface and registering them in the ImageRegistry.

The defineImage() methods return an Definition (the abstract base class for all objects used to define shapes etc. in a Flash file. The exact class of the object generated depends of the format of the image loaded.

Class	Generated when...
DefineJPEGImage2	A JPEG encoded image is loaded. The getFormat() method returns the class constant JPEG.
DefineImage	An indexed BMP or PNG image contains a colour table without transparent colours or when a true colour image contains 16-bit or 24-bit colours is loaded. The getFormat() method returns the class constants IDX8, RGB5 or RGB8.
DefineImage2	A BMP or PNG indexed image contains a colour table with transparent colours is loaded or when a true colour image contains 32-bit bit colours. The getFormat() method returns the class constants IDXA or RGBA.

Images are displayed in Flash by filling a shape with the image bitmap. The defineEnclosingShape() method generates a rectangular shape object which wraps the image:

     int imageId = movie.newIdentifier();
     int shapeId = movie.newIdentifier();

     Definition image = Image(defineImage(imageId, ...);

     int x = image.getWidth()/2;
     int y = image.getHeight()/2;

     LineStyle style = new LineStyle(20, ColorTable.black());

     movie.add(image);
     movie.add(Image.defineEnclosingShape(shapeId, image, x, y, style);
 

Here the origin, used when placing the shape on the screen, is defined as the centre of the shape. Other points may be defined to suit the alignment of the shape when it is placed on the display list.

Constructor Summary

ImageFactory()

Method Summary

ImageTag	defineImage(int identifier) Create a definition for the image so it can be added to a Flash movie.
ImageDecoder	getDecoder() Get the ImageDecoder used to decode the image.
void	read(File file) Create an image definition for the image located in the specified file.
void	read(InputStream stream) Create an image definition for an image read from a stream.
void	read(URL url) Create an image definition for the image referenced by a URL.

Methods inherited from class java.lang.Object

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

Constructor Detail

ImageFactory

public ImageFactory()

Method Detail

read

public void read(File file)
          throws IOException,
                 DataFormatException

Create an image definition for the image located in the specified file.

Parameters:

file - a file containing the abstract path to the image.

Throws:

IOException - if there is an error reading the file.

DataFormatException - if there is a problem decoding the image, either it is in an unsupported format or an error occurred while decoding the image data.

read

public void read(URL url)
          throws IOException,
                 DataFormatException

Create an image definition for the image referenced by a URL.

Parameters:

url - the Uniform Resource Locator referencing the file.

Throws:

IOException - if there is an error reading the file.

DataFormatException - if there is a problem decoding the image, either it is in an unsupported format or an error occurred while decoding the image data.

read

public void read(InputStream stream)
          throws IOException,
                 DataFormatException

Create an image definition for an image read from a stream.

Parameters:

stream - the InputStream containing the image data.

Throws:

IOException - if there is an error reading the stream.

DataFormatException - if there is a problem decoding the image, either it is in an unsupported format or an error occurred while decoding the image data.

defineImage

public ImageTag defineImage(int identifier)

Create a definition for the image so it can be added to a Flash movie.

Parameters:

identifier - the unique identifier for the image.

Returns:

an ImageTag representing one of the image definitions supported in Flash.

getDecoder

public ImageDecoder getDecoder()

Get the ImageDecoder used to decode the image.

Returns:

the ImageDecoder instance that the factory created to decode the image.