Package org.openpdf.text.pdf.parser

Class PdfContentStreamHandler

java.lang.Object

org.openpdf.text.pdf.parser.PdfContentStreamHandler

Direct Known Subclasses:

PdfContentTextExtractor, PdfContentTextLocator

public abstract class PdfContentStreamHandler
extends Object

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	PdfContentStreamHandler.BeginMarked	A content operator implementation (BMC).
private static class	PdfContentStreamHandler.BeginMarkedDict	A content operator implementation (BDC).
(package private) static class	PdfContentStreamHandler.BeginText	A content operator implementation (BT).
protected class	PdfContentStreamHandler.Do	A content operator implementation (Do) for handling XObject forms.
private static class	PdfContentStreamHandler.EndMarked	A content operator implementation (EMC).
(package private) static class	PdfContentStreamHandler.EndText	A content operator implementation (ET).
(package private) static class	PdfContentStreamHandler.ModifyCurrentTransformationMatrix	A content operator implementation (cm).
(package private) static class	PdfContentStreamHandler.MoveNextLineAndShowText	A content operator implementation (').
(package private) static class	PdfContentStreamHandler.MoveNextLineAndShowTextWithSpacing	A content operator implementation (").
(package private) static class	PdfContentStreamHandler.PopGraphicsState	A content operator implementation (Q).
(package private) static class	PdfContentStreamHandler.ProcessGraphicsStateResource	A content operator implementation (gs).
(package private) static class	PdfContentStreamHandler.PushGraphicsState	A content operator implementation (q).
(package private) static class	PdfContentStreamHandler.SetTextCharacterSpacing	A content operator implementation (Tc).
(package private) static class	PdfContentStreamHandler.SetTextFont	A content operator implementation (Tf).
(package private) static class	PdfContentStreamHandler.SetTextHorizontalScaling	A content operator implementation (Tz).
(package private) static class	PdfContentStreamHandler.SetTextLeading	A content operator implementation (TL).
(package private) static class	PdfContentStreamHandler.SetTextRenderMode	A content operator implementation (Tr).
(package private) static class	PdfContentStreamHandler.SetTextRise	A content operator implementation (Ts).
(package private) static class	PdfContentStreamHandler.SetTextWordSpacing	A content operator implementation (Tw).
(package private) static class	PdfContentStreamHandler.ShowText	A content operator implementation (Tj).
(package private) static class	PdfContentStreamHandler.ShowTextArray	A content operator implementation (TJ).
(package private) static class	PdfContentStreamHandler.TextMoveNextLine	A content operator implementation (T*).
(package private) static class	PdfContentStreamHandler.TextMoveStartNextLine	A content operator implementation (Td).
(package private) static class	PdfContentStreamHandler.TextMoveStartNextLineWithLeading	A content operator implementation (TD).
(package private) static class	PdfContentStreamHandler.TextSetTextMatrix	A content operator implementation (Tm).

Field Summary

Fields

Modifier and Type	Field	Description
protected final Stack<String>	contextNames
protected Stack<GraphicsState>	gsStack	Stack keeping track of the graphics state.
protected Map<String,ContentOperator>	operators	A map with all supported operators operators (PDF syntax).
protected final TextAssembler	renderListener	detail parser for text within a marked section.
protected List<TextAssemblyBuffer>	textFragments
protected final Stack<List<TextAssemblyBuffer>>	textFragmentStreams
protected Matrix	textLineMatrix	Text line matrix.
protected Matrix	textMatrix	Text matrix.

Constructor Summary

Constructors

Constructor	Description
PdfContentStreamHandler(TextAssembler renderListener)

Method Summary

Modifier and Type	Method	Description
(package private) void	applyTextAdjust(float tj)	Adjusts the text matrix for the specified adjustment value (see TJ operator in the PDF spec for information)
(package private) abstract void	displayPdfString(PdfString string)	Displays text.
protected byte[]	getContentBytesFromPdfObject(PdfObject object)	Gets the content bytes from a PdfObject, which may be a reference, a stream or an array.
(package private) static byte[]	getContentBytesFromPdfObjectStatic(PdfObject object)	Gets the content bytes from a PdfObject, which may be a reference, a stream or an array.
CMapAwareDocumentFont	getCurrentFont()
protected Matrix	getCurrentTextLineMatrix()	Returns the current line matrix.
protected Matrix	getCurrentTextMatrix()	Returns the current text matrix.
private static Matrix	getMatrix(List<PdfObject> operands)
abstract String	getResultantText()
(package private) GraphicsState	graphicsState()	Returns the current graphics state.
protected void	installDefaultOperators()	Loads all the supported graphics and text state operators in a map.
void	invokeOperator(PdfLiteral operator, List<PdfObject> operands, PdfDictionary resources)	Invokes an operator.
protected Optional<ContentOperator>	lookupOperator(String operatorName)	Get the operator to process a command with a given name
(package private) abstract void	popContext()
protected void	processContent(byte[] contentBytes, PdfDictionary resources)	Processes PDF content stream bytes.
(package private) abstract void	pushContext(String newContextName)
void	registerContentOperator(ContentOperator operator)	Registers a content operator that will be called when the specified operator string is encountered during content processing.
abstract void	reset()

Methods inherited from class java.lang.Object

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

Field Details

textFragmentStreams

protected final Stack<List<TextAssemblyBuffer>> textFragmentStreams

contextNames

protected final Stack<String> contextNames

renderListener

protected final TextAssembler renderListener

detail parser for text within a marked section. used by TextAssembler

operators

protected Map<String,ContentOperator> operators

A map with all supported operators operators (PDF syntax). Protected to allow subclasses to override installDefaultOperators() and register additional operators.

gsStack

protected Stack<GraphicsState> gsStack

Stack keeping track of the graphics state.

textMatrix

protected Matrix textMatrix

Text matrix.

textLineMatrix

protected Matrix textLineMatrix

Text line matrix.

textFragments

protected List<TextAssemblyBuffer> textFragments

Constructor Details

PdfContentStreamHandler

public PdfContentStreamHandler(TextAssembler renderListener)

Method Details

getMatrix

private static Matrix getMatrix(List<PdfObject> operands)

registerContentOperator

public void registerContentOperator(ContentOperator operator)

Registers a content operator that will be called when the specified operator string is encountered during content processing. Each operator may be registered only once (it is not legal to have multiple operators with the same operatorString)

Parameters:

operator - the operator that will receive notification when the operator is encountered

Since:

2.1.7

installDefaultOperators

protected void installDefaultOperators()

Loads all the supported graphics and text state operators in a map. Subclasses can override this method to register additional operators. When overriding, subclasses should call super.installDefaultOperators() first.

lookupOperator

protected Optional<ContentOperator> lookupOperator(String operatorName)

Get the operator to process a command with a given name

Parameters:

operatorName - name of the operator that we might need to call

Returns:

the operator or null if none present

invokeOperator

public void invokeOperator(PdfLiteral operator,
 List<PdfObject> operands,
 PdfDictionary resources)

Invokes an operator.

Parameters:

operator - the PDF Syntax of the operator

operands - a list with operands

resources - Pdf Resources found in the file containing the stream.

popContext

abstract void popContext()

pushContext

abstract void pushContext(String newContextName)

graphicsState

GraphicsState graphicsState()

Returns the current graphics state.

Returns:

the graphics state

reset

public abstract void reset()

getCurrentTextMatrix

protected Matrix getCurrentTextMatrix()

Returns the current text matrix.

Returns:

the text matrix

Since:

2.1.5

getCurrentTextLineMatrix

protected Matrix getCurrentTextLineMatrix()

Returns the current line matrix.

Returns:

the line matrix

Since:

2.1.5

applyTextAdjust

void applyTextAdjust(float tj)

Adjusts the text matrix for the specified adjustment value (see TJ operator in the PDF spec for information)

Parameters:

tj - the text adjustment

getCurrentFont

public CMapAwareDocumentFont getCurrentFont()

Returns:

current font in processing state

displayPdfString

abstract void displayPdfString(PdfString string)

Displays text.

Parameters:

string - the text to display

getResultantText

public abstract String getResultantText()

Returns:

result text

processContent

protected void processContent(byte[] contentBytes,
 PdfDictionary resources)

Processes PDF content stream bytes.

Parameters:

contentBytes - the bytes of a content stream

resources - the resources that come with the content stream

getContentBytesFromPdfObject

protected byte[] getContentBytesFromPdfObject(PdfObject object)
                                       throws IOException

Gets the content bytes from a PdfObject, which may be a reference, a stream or an array. This is a utility method that can be used by subclasses and other classes in this package.

Parameters:

object - the object to read bytes from

Returns:

the content bytes

Throws:

IOException - if there's an error reading the content

getContentBytesFromPdfObjectStatic

static byte[] getContentBytesFromPdfObjectStatic(PdfObject object)
                                          throws IOException

Gets the content bytes from a PdfObject, which may be a reference, a stream or an array. This is a static utility method that can be used by any class in this package.

Parameters:

object - the object to read bytes from

Returns:

the content bytes

Throws:

IOException - if there's an error reading the content