org.foray.graphic
Class PNGGraphic

java.lang.Object
  org.foray.graphic.Graphic4a
      org.foray.graphic.PNGGraphic

All Implemented Interfaces:

org.axsl.graphic.Graphic

public class PNGGraphic
extends Graphic4a

A PNG (Portable Network Graphics) images.

Nested Class Summary

Nested classes/interfaces inherited from interface org.axsl.graphic.Graphic

org.axsl.graphic.Graphic.Compression, org.axsl.graphic.Graphic.Type

Field Summary

protected static byte	PIXEL_HEIGHT_STARTS Constant indicating the location of the first byte (of four) in the file indicating the pixel height.
protected static byte	PIXEL_WIDTH_STARTS Constant indicating the location of the first byte (of four) in the file indicating the pixel width.
static int	PNG_BASICS_LENGTH The number of bytes that need to be read to get the basic information for a PNG file.

Fields inherited from class org.foray.graphic.Graphic4a

BIT_DEPTH_4, BIT_DEPTH_COLOR, BIT_DEPTH_GRAYSCALE, BIT_DEPTH_MONOCHROME

Constructor Summary

PNGGraphic(GraphicServer4a server, URL url, BufferedInputStream bis)
Constructor.

Method Summary

int	absoluteHeightReal() Returns the absolute height, in millipoints, of the graphic.
int	absoluteWidthReal() Returns the absolute width, in millipoints, of the graphic.
protected org.apache.xmlgraphics.image.rendered.CachableRed	decodeImage(org.apache.xmlgraphics.image.codec.util.SeekableStream stream) Decodes the image from the stream.
ColorSpace	getColorSpace()
org.axsl.graphic.Graphic.Compression	getCompressionType()
org.axsl.graphic.Graphic.Type	getGraphicType()
String	getMimeType()
String	getName()
byte[]	getRawSamples()
org.apache.xmlgraphics.image.codec.util.SeekableStream	getSeekableInput() Returns the seekable input.
Color	getTransparentColor()
boolean	isInverted()
boolean	isTransparent()
protected void	loadImage() Load image data and initialize its properties.
void	parseBasics() This abstract method is implemented in subclasses to initiate parsing of enough of the image for it to be used in layout.
int	pixelHeight()
int	pixelWidth()

Methods inherited from class org.foray.graphic.Graphic4a

absoluteHeight, absoluteWidth, canMakeGraphicOutput, close, getBitDepth, getBitsPerComponent, getContent, getContentSize, getGraphicOutput, getInputStream, getLinks, getLogger, getRawColorSpace, getServer, getUrl, isImageLoaded, isValid, loadImageWrapper, maxBytesToParseBasics, parseBasicsWrapper, setBasicsParsed, setBitDepth, setContent, setImageLoaded, setInputStream, setLinks, setValid

Methods inherited from class java.lang.Object

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

Field Detail

PNG_BASICS_LENGTH

public static final int PNG_BASICS_LENGTH

The number of bytes that need to be read to get the basic information for a PNG file.

See Also:

Constant Field Values

PIXEL_WIDTH_STARTS

protected static final byte PIXEL_WIDTH_STARTS

Constant indicating the location of the first byte (of four) in the file indicating the pixel width.

See Also:

Constant Field Values

PIXEL_HEIGHT_STARTS

protected static final byte PIXEL_HEIGHT_STARTS

Constant indicating the location of the first byte (of four) in the file indicating the pixel height.

See Also:

Constant Field Values

Constructor Detail

PNGGraphic

public PNGGraphic(GraphicServer4a server,
                  URL url,
                  BufferedInputStream bis)

Constructor.

Parameters:

server - The parent graphic server.

url - The URL which contains the graphic content.

bis - The reusable input stream containing the bytes from url.

Method Detail

getMimeType

public String getMimeType()

getName

public String getName()

getCompressionType

public org.axsl.graphic.Graphic.Compression getCompressionType()
                                                        throws org.axsl.graphic.GraphicException

Throws:

org.axsl.graphic.GraphicException

getGraphicType

public org.axsl.graphic.Graphic.Type getGraphicType()

parseBasics

public void parseBasics()
                 throws IOException

Description copied from class: Graphic4a

This abstract method is implemented in subclasses to initiate parsing of enough of the image for it to be used in layout. This method is responsible to:

1. store the image's intrinsic width in Graphic.pixelWidth()
2. store the image's intrinsic height in Graphic.pixelHeight()

The housekeeping work related to resetting the buffer, handling IOExceptions, and managing whether this method should be run are handled elsewhere. In short, this method does not need to address the details handled there.

Specified by:

parseBasics in class Graphic4a

Throws:

IOException - For IO errors during reading of the file.

decodeImage

protected org.apache.xmlgraphics.image.rendered.CachableRed decodeImage(org.apache.xmlgraphics.image.codec.util.SeekableStream stream)
                                                                 throws IOException

Decodes the image from the stream.

Parameters:

stream - the stream to read the image from

Returns:

the decoded image

Throws:

IOException - in case an I/O problem occurs

loadImage

protected void loadImage()
                  throws org.axsl.graphic.GraphicException

Description copied from class: Graphic4a

Load image data and initialize its properties. Subclasses need to implement this method.

Specified by:

loadImage in class Graphic4a

Throws:

org.axsl.graphic.GraphicException - an error occured during loading

getSeekableInput

public org.apache.xmlgraphics.image.codec.util.SeekableStream getSeekableInput()

Returns the seekable input.

Returns:

The seekableInput.

getRawSamples

public byte[] getRawSamples()
                     throws org.axsl.graphic.GraphicException

Throws:

org.axsl.graphic.GraphicException

absoluteWidthReal

public int absoluteWidthReal()
                      throws org.axsl.graphic.GraphicException

Description copied from class: Graphic4a

Returns the absolute width, in millipoints, of the graphic.

Specified by:

absoluteWidthReal in class Graphic4a

Returns:

The absolute width, in millipoints, of this graphic, if known. If not known, returns -1.

Throws:

org.axsl.graphic.GraphicException - For errors during reading of image file.

absoluteHeightReal

public int absoluteHeightReal()
                       throws org.axsl.graphic.GraphicException

Description copied from class: Graphic4a

Returns the absolute height, in millipoints, of the graphic.

Specified by:

absoluteHeightReal in class Graphic4a

Returns:

The absolute height, in millipoints, of this graphic, if known. If not known, returns -1.

Throws:

org.axsl.graphic.GraphicException - For errors during reading of image file.

isInverted

public boolean isInverted()

getColorSpace

public ColorSpace getColorSpace()
                         throws org.axsl.graphic.GraphicException

Throws:

org.axsl.graphic.GraphicException

isTransparent

public boolean isTransparent()
                      throws org.axsl.graphic.GraphicException

Throws:

org.axsl.graphic.GraphicException

getTransparentColor

public Color getTransparentColor()
                          throws org.axsl.graphic.GraphicException

Throws:

org.axsl.graphic.GraphicException

pixelWidth

public int pixelWidth()
               throws org.axsl.graphic.GraphicException

Throws:

org.axsl.graphic.GraphicException

pixelHeight

public int pixelHeight()
                throws org.axsl.graphic.GraphicException

Throws:

org.axsl.graphic.GraphicException