org.apache.fop.pdf
Class PDFXObject

java.lang.Object
  org.apache.fop.pdf.PDFObject
      org.apache.fop.pdf.AbstractPDFStream
          org.apache.fop.pdf.PDFXObject

Direct Known Subclasses:

PDFFormXObject

public class PDFXObject

extends AbstractPDFStream

PDF XObject A derivative of the PDF Object, is a PDF Stream that has not only a dictionary but a stream of image data. The dictionary just provides information like the stream length. This outputs the image dictionary and the image data. This is used as a reference for inserting the same image in the document in another place.

Field Summary

Fields inherited from class org.apache.fop.pdf.PDFObject

DATE_FORMAT, log

Constructor Summary

PDFXObject(int xnumber, PDFImage img)
create an XObject with the given number and name and load the image in the object

Method Summary

protected java.lang.String	buildStreamDict(java.lang.String lengthEntry) Constructs the dictionary for the stream.
protected int	getSizeHint() Returns a value that hints at the size of the encoded stream.
int	getXNumber() Get the xnumber for this pdf object.
protected int	output(java.io.OutputStream stream) Output the image as PDF.
protected void	outputRawStreamData(java.io.OutputStream out) Sends the raw stream data to the target OutputStream.
protected void	prepareImplicitFilters() Prepares implicit filters (such as the DCTFilter for JPEG images).
protected void	setupFilterList() This sets up the default filters for XObjects.

Methods inherited from class org.apache.fop.pdf.AbstractPDFStream

encodeAndWriteStream, encodeStream, getFilterList, outputStreamData

Methods inherited from class org.apache.fop.pdf.PDFObject

encode, encodeString, encodeText, formatDateTime, getDocument, getDocumentSafely, getGeneration, getObjectID, getObjectNumber, hasObjectNumber, referencePDF, setDocument, setObjectNumber, toPDF, toPDFString

Methods inherited from class java.lang.Object

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

Constructor Detail

PDFXObject

public PDFXObject(int xnumber,
                  PDFImage img)

create an XObject with the given number and name and load the image in the object

Parameters:

xnumber - the pdf object X number

img - the pdf image that contains the image data

Method Detail

getXNumber

public int getXNumber()

Get the xnumber for this pdf object.

Returns:

the PDF XObject number

output

protected int output(java.io.OutputStream stream)
              throws java.io.IOException

Output the image as PDF. This sets up the image dictionary and adds the image data stream.

Overrides:

output in class AbstractPDFStream

Parameters:

stream - the output stream to write the data

Returns:

the length of the data written

Throws:

java.io.IOException - if there is an error writing the data

See Also:

PDFObject.output(OutputStream)

buildStreamDict

protected java.lang.String buildStreamDict(java.lang.String lengthEntry)

Description copied from class: AbstractPDFStream

Constructs the dictionary for the stream. Override this method if you need additional entries.

Overrides:

buildStreamDict in class AbstractPDFStream

Parameters:

lengthEntry - value for the /Length entry

Returns:

the newly constructed dictionary

See Also:

AbstractPDFStream.buildStreamDict(String)

outputRawStreamData

protected void outputRawStreamData(java.io.OutputStream out)
                            throws java.io.IOException

Description copied from class: AbstractPDFStream

Sends the raw stream data to the target OutputStream.

Specified by:

outputRawStreamData in class AbstractPDFStream

Parameters:

out - OutputStream to write to

Throws:

java.io.IOException - In case of an I/O problem

See Also:

PDFStream.outputRawStreamData(OutputStream)

getSizeHint

protected int getSizeHint()
                   throws java.io.IOException

Description copied from class: AbstractPDFStream

Returns a value that hints at the size of the encoded stream. This is used to optimize buffer allocation so fewer buffer reallocations are necessary.

Specified by:

getSizeHint in class AbstractPDFStream

Returns:

an estimated size (0 if no hint can be given)

Throws:

java.io.IOException - in case of an I/O problem

See Also:

AbstractPDFStream.getSizeHint()

prepareImplicitFilters

protected void prepareImplicitFilters()

Description copied from class: AbstractPDFStream

Prepares implicit filters (such as the DCTFilter for JPEG images). You must make sure that the appropriate filters are in the filter list at the right places.

Overrides:

prepareImplicitFilters in class AbstractPDFStream

See Also:

AbstractPDFStream.prepareImplicitFilters()

setupFilterList

protected void setupFilterList()

This sets up the default filters for XObjects. It uses the PDFImage instance to determine what default filters to apply.

Overrides:

setupFilterList in class AbstractPDFStream

See Also:

AbstractPDFStream.setupFilterList()