Module org.sejda.sambox

Package org.sejda.sambox.text

Class PDFTextStreamEngine

java.lang.Object

org.sejda.sambox.contentstream.PDFStreamEngine

org.sejda.sambox.text.PDFTextStreamEngine

Direct Known Subclasses:

PDFMarkedContentExtractor, PDFTextStripper

public class PDFTextStreamEngine
extends PDFStreamEngine

PDFStreamEngine subclass for advanced processing of text via TextPosition.

Author:

Ben Litchfield, John Hewson

See Also:

• TextPosition

Constructor Summary

Constructors

Constructor	Description
PDFTextStreamEngine()	Constructor.

Method Summary

Modifier and Type	Method	Description
protected float	computeFontHeight(PDFont font)	Compute the font height.
void	processPage(PDPage page)	This will initialise and process the contents of the stream.
protected void	processTextPosition(TextPosition text)	A method provided as an event interface to allow a subclass to perform some specific functionality when text needs to be processed.
protected void	showGlyph(Matrix textRenderingMatrix, PDFont font, int code, Vector displacement)	Called when a glyph is to be processed.

Methods inherited from class org.sejda.sambox.contentstream.PDFStreamEngine

addOperator, addOperatorIfAbsent, applyTextAdjustment, beginMarkedContentSequence, beginText, decreaseLevel, endMarkedContentSequence, endText, getAppearance, getCurrentPage, getGraphicsStackSize, getGraphicsState, getInitialMatrix, getLevel, getResources, getTextLineMatrix, getTextMatrix, increaseLevel, operatorException, processAnnotation, processChildStream, processOperator, processOperator, processSoftMask, processStream, processTilingPattern, processTilingPattern, processTransparencyGroup, processType3Stream, restoreGraphicsStack, restoreGraphicsState, saveGraphicsStack, saveGraphicsState, setLineDashPattern, setTextLineMatrix, setTextMatrix, showAnnotation, showFontGlyph, showForm, showText, showTextString, showTextStrings, showTransparencyGroup, showType3Glyph, transformedPoint, transformWidth, unsupportedOperator

Methods inherited from class java.lang.Object

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

Constructor Details

PDFTextStreamEngine

public PDFTextStreamEngine()
                    throws IOException

Constructor.

Throws:

IOException

Method Details

processPage

public void processPage(PDPage page)
                 throws IOException

This will initialise and process the contents of the stream.

Overrides:

processPage in class PDFStreamEngine

Parameters:

page - the page to process

Throws:

IOException - if there is an error accessing the stream.

showGlyph

protected void showGlyph(Matrix textRenderingMatrix,
 PDFont font,
 int code,
 Vector displacement)
                  throws IOException

Called when a glyph is to be processed. The heuristic calculations here were originally written by Ben Litchfield for PDFStreamEngine.

Overrides:

showGlyph in class PDFStreamEngine

Parameters:

textRenderingMatrix - the current text rendering matrix, T_rm

font - the current font

code - internal PDF character code for the glyph

displacement - the displacement (i.e. advance) of the glyph in text space

Throws:

IOException - if the glyph cannot be processed

computeFontHeight

protected float computeFontHeight(PDFont font)
                           throws IOException

Compute the font height. Override this if you want to use own calculations.

Parameters:

font - the font.

Returns:

the font height.

Throws:

IOException - if there is an error while getting the font bounding box.

processTextPosition

protected void processTextPosition(TextPosition text)

A method provided as an event interface to allow a subclass to perform some specific functionality when text needs to be processed.

Parameters:

text - The text to be processed.