Package org.apache.pdfbox.contentstream
Class PDFStreamEngine
- java.lang.Object
-
- org.apache.pdfbox.contentstream.PDFStreamEngine
-
- Direct Known Subclasses:
LegacyPDFStreamEngine,PDFGraphicsStreamEngine,PreflightStreamEngine
public abstract class PDFStreamEngine extends java.lang.ObjectProcesses a PDF content stream and executes certain operations. Provides a callback interface for clients that want to do things with the stream.
-
-
Field Summary
Fields Modifier and Type Field Description private PDPagecurrentPageprivate PDFontdefaultFontprivate java.util.Deque<PDGraphicsState>graphicsStackprivate MatrixinitialMatrixprivate booleanisProcessingPageprivate intlevelprivate static org.apache.commons.logging.LogLOGprivate java.util.Map<java.lang.String,OperatorProcessor>operatorsprivate PDResourcesresourcesprivate booleanshouldProcessColorOperators
-
Constructor Summary
Constructors Modifier Constructor Description protectedPDFStreamEngine()Creates a new PDFStreamEngine.
-
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description voidaddOperator(OperatorProcessor op)Adds an operator processor to the engine.protected voidapplyTextAdjustment(float tx, float ty)Applies a text position adjustment from the TJ operator.voidbeginMarkedContentSequence(COSName tag, COSDictionary properties)Called when a marked content group beginsvoidbeginText()Called when the BT operator is encountered.private voidclipToRect(PDRectangle rectangle)Transforms the given rectangle using the CTM and then intersects it with the current clipping area.voiddecreaseLevel()Decrease the level.voidendMarkedContentSequence()Called when a marked content group endsvoidendText()Called when the ET operator is encountered.PDAppearanceStreamgetAppearance(PDAnnotation annotation)Returns the appearance stream to process for the given annotation.PDPagegetCurrentPage()Returns the current page.private PDFontgetDefaultFont()Provide standard 14 Helvetica font as default if there isn't any font available.intgetGraphicsStackSize()PDGraphicsStategetGraphicsState()MatrixgetInitialMatrix()Gets the stream's initial matrix.intgetLevel()Get the current level.PDResourcesgetResources()MatrixgetTextLineMatrix()MatrixgetTextMatrix()voidincreaseLevel()Increase the level.private voidinitPage(PDPage page)Initializes the stream engine for the given page.booleanisShouldProcessColorOperators()Tells whether color operators should be processed.voidmarkedContentPoint(COSName tag, COSDictionary properties)Handles MP and DP operators.protected voidoperatorException(Operator operator, java.util.List<COSBase> operands, java.io.IOException exception)Called when an exception is thrown by an operator.private voidpopResources(PDResources parentResources)Pops the current resources, replacing them with the given resources.protected voidprocessAnnotation(PDAnnotation annotation, PDAppearanceStream appearance)Process the given annotation with the specified appearance stream.protected voidprocessChildStream(PDContentStream contentStream, PDPage page)Process a child stream of the given page.voidprocessOperator(java.lang.String operation, java.util.List<COSBase> arguments)This is used to handle an operation.protected voidprocessOperator(Operator operator, java.util.List<COSBase> operands)This is used to handle an operation.voidprocessPage(PDPage page)This will initialize and process the contents of the stream.protected voidprocessSoftMask(PDTransparencyGroup group)Processes a soft mask transparency group stream.private voidprocessStream(PDContentStream contentStream)Process a content stream.private voidprocessStreamOperators(PDContentStream contentStream)Processes the operators of the given content stream.protected voidprocessTilingPattern(PDTilingPattern tilingPattern, PDColor color, PDColorSpace colorSpace)Process the given tiling pattern.protected voidprocessTilingPattern(PDTilingPattern tilingPattern, PDColor color, PDColorSpace colorSpace, Matrix patternMatrix)Process the given tiling pattern.protected voidprocessTransparencyGroup(PDTransparencyGroup group)Processes a transparency group stream.protected voidprocessType3Stream(PDType3CharProc charProc, Matrix textRenderingMatrix)Processes a Type 3 character stream.private PDResourcespushResources(PDContentStream contentStream)Pushes the given stream's resources, returning the previous resources.protected voidrestoreGraphicsStack(java.util.Deque<PDGraphicsState> snapshot)Restores the entire graphics stack.voidrestoreGraphicsState()Pops the current graphics state from the stack.protected java.util.Deque<PDGraphicsState>saveGraphicsStack()Saves the entire graphics stack.voidsaveGraphicsState()Pushes the current graphics state to the stack.voidsetLineDashPattern(COSArray array, int phase)voidsetTextLineMatrix(Matrix value)voidsetTextMatrix(Matrix value)voidshowAnnotation(PDAnnotation annotation)Shows the given annotation.protected voidshowFontGlyph(Matrix textRenderingMatrix, PDFont font, int code, Vector displacement)Called when a glyph is to be processed.voidshowForm(PDFormXObject form)Shows a form from the content stream.protected voidshowGlyph(Matrix textRenderingMatrix, PDFont font, int code, Vector displacement)Called when a glyph is to be processed.protected voidshowText(byte[] string)Process text from the PDF Stream.voidshowTextString(byte[] string)Called when a string of text is to be shown.voidshowTextStrings(COSArray array)Called when a string of text with spacing adjustments is to be shown.voidshowTransparencyGroup(PDTransparencyGroup form)Shows a transparency group from the content stream.protected voidshowType3Glyph(Matrix textRenderingMatrix, PDType3Font font, int code, Vector displacement)Called when a glyph is to be processed.java.awt.geom.Point2D.FloattransformedPoint(float x, float y)Transforms a point using the CTM.protected floattransformWidth(float width)Transforms a width using the CTM.protected voidunsupportedOperator(Operator operator, java.util.List<COSBase> operands)Called when an unsupported operator is encountered.
-
-
-
Field Detail
-
LOG
private static final org.apache.commons.logging.Log LOG
-
operators
private final java.util.Map<java.lang.String,OperatorProcessor> operators
-
graphicsStack
private java.util.Deque<PDGraphicsState> graphicsStack
-
resources
private PDResources resources
-
currentPage
private PDPage currentPage
-
isProcessingPage
private boolean isProcessingPage
-
initialMatrix
private Matrix initialMatrix
-
level
private int level
-
defaultFont
private PDFont defaultFont
-
shouldProcessColorOperators
private boolean shouldProcessColorOperators
-
-
Method Detail
-
addOperator
public final void addOperator(OperatorProcessor op)
Adds an operator processor to the engine.- Parameters:
op- operator processor
-
initPage
private void initPage(PDPage page)
Initializes the stream engine for the given page.
-
getDefaultFont
private PDFont getDefaultFont()
Provide standard 14 Helvetica font as default if there isn't any font available.- Returns:
- the default font
-
processPage
public void processPage(PDPage page) throws java.io.IOException
This will initialize and process the contents of the stream.- Parameters:
page- the page to process- Throws:
java.io.IOException- if there is an error accessing the stream
-
showTransparencyGroup
public void showTransparencyGroup(PDTransparencyGroup form) throws java.io.IOException
Shows a transparency group from the content stream.- Parameters:
form- transparency group (form) XObject- Throws:
java.io.IOException- if the transparency group cannot be processed
-
showForm
public void showForm(PDFormXObject form) throws java.io.IOException
Shows a form from the content stream.- Parameters:
form- form XObject- Throws:
java.io.IOException- if the form cannot be processed
-
processSoftMask
protected void processSoftMask(PDTransparencyGroup group) throws java.io.IOException
Processes a soft mask transparency group stream.- Parameters:
group- transparency group used for the soft mask- Throws:
java.io.IOException- if the transparency group cannot be processed
-
processTransparencyGroup
protected void processTransparencyGroup(PDTransparencyGroup group) throws java.io.IOException
Processes a transparency group stream.- Parameters:
group- transparency group to be processed- Throws:
java.io.IOException- if the transparency group cannot be processed
-
processType3Stream
protected void processType3Stream(PDType3CharProc charProc, Matrix textRenderingMatrix) throws java.io.IOException
Processes a Type 3 character stream.- Parameters:
charProc- Type 3 character proceduretextRenderingMatrix- the Text Rendering Matrix- Throws:
java.io.IOException- if there is an error reading or parsing the character content stream.
-
processAnnotation
protected void processAnnotation(PDAnnotation annotation, PDAppearanceStream appearance) throws java.io.IOException
Process the given annotation with the specified appearance stream.- Parameters:
annotation- The annotation containing the appearance stream to process.appearance- The appearance stream to process.- Throws:
java.io.IOException- If there is an error reading or parsing the appearance content stream.
-
processTilingPattern
protected final void processTilingPattern(PDTilingPattern tilingPattern, PDColor color, PDColorSpace colorSpace) throws java.io.IOException
Process the given tiling pattern.- Parameters:
tilingPattern- the tiling patterncolor- color to use, if this is an uncoloured pattern, otherwise null.colorSpace- color space to use, if this is an uncoloured pattern, otherwise null.- Throws:
java.io.IOException- if there is an error reading or parsing the tiling pattern content stream.
-
processTilingPattern
protected final void processTilingPattern(PDTilingPattern tilingPattern, PDColor color, PDColorSpace colorSpace, Matrix patternMatrix) throws java.io.IOException
Process the given tiling pattern. Allows the pattern matrix to be overridden for custom rendering.- Parameters:
tilingPattern- the tiling patterncolor- color to use, if this is an uncoloured pattern, otherwise null.colorSpace- color space to use, if this is an uncoloured pattern, otherwise null.patternMatrix- the pattern matrix, may be overridden for custom rendering.- Throws:
java.io.IOException- if there is an error reading or parsing the tiling pattern content stream.
-
showAnnotation
public void showAnnotation(PDAnnotation annotation) throws java.io.IOException
Shows the given annotation.- Parameters:
annotation- An annotation on the current page.- Throws:
java.io.IOException- If an error occurred reading the annotation
-
getAppearance
public PDAppearanceStream getAppearance(PDAnnotation annotation)
Returns the appearance stream to process for the given annotation. May be used to render a specific appearance such as "hover".- Parameters:
annotation- The current annotation.- Returns:
- The stream to process.
-
processChildStream
protected void processChildStream(PDContentStream contentStream, PDPage page) throws java.io.IOException
Process a child stream of the given page. Cannot be used withprocessPage(PDPage).- Parameters:
contentStream- the child content streampage- the page to be used for processing- Throws:
java.io.IOException- if there is an exception while processing the stream
-
processStream
private void processStream(PDContentStream contentStream) throws java.io.IOException
Process a content stream.- Parameters:
contentStream- the content stream- Throws:
java.io.IOException- if there is an exception while processing the stream
-
processStreamOperators
private void processStreamOperators(PDContentStream contentStream) throws java.io.IOException
Processes the operators of the given content stream.- Parameters:
contentStream- to content stream to parse.- Throws:
java.io.IOException- if there is an error reading or parsing the content stream.
-
pushResources
private PDResources pushResources(PDContentStream contentStream)
Pushes the given stream's resources, returning the previous resources.
-
popResources
private void popResources(PDResources parentResources)
Pops the current resources, replacing them with the given resources.
-
clipToRect
private void clipToRect(PDRectangle rectangle)
Transforms the given rectangle using the CTM and then intersects it with the current clipping area.
-
beginText
public void beginText() throws java.io.IOExceptionCalled when the BT operator is encountered. This method is for overriding in subclasses, the default implementation does nothing.- Throws:
java.io.IOException- if there was an error processing the text
-
endText
public void endText() throws java.io.IOExceptionCalled when the ET operator is encountered. This method is for overriding in subclasses, the default implementation does nothing.- Throws:
java.io.IOException- if there was an error processing the text
-
showTextString
public void showTextString(byte[] string) throws java.io.IOExceptionCalled when a string of text is to be shown.- Parameters:
string- the encoded text- Throws:
java.io.IOException- if there was an error showing the text
-
showTextStrings
public void showTextStrings(COSArray array) throws java.io.IOException
Called when a string of text with spacing adjustments is to be shown.- Parameters:
array- array of encoded text strings and adjustments- Throws:
java.io.IOException- if there was an error showing the text
-
applyTextAdjustment
protected void applyTextAdjustment(float tx, float ty)Applies a text position adjustment from the TJ operator. May be overridden in subclasses.- Parameters:
tx- x-translationty- y-translation
-
showText
protected void showText(byte[] string) throws java.io.IOExceptionProcess text from the PDF Stream. You should override this method if you want to perform an action when encoded text is being processed.- Parameters:
string- the encoded text- Throws:
java.io.IOException- if there is an error processing the string
-
showGlyph
protected void showGlyph(Matrix textRenderingMatrix, PDFont font, int code, Vector displacement) throws java.io.IOException
Called when a glyph is to be processed. This method is intended for overriding in subclasses, the default implementation does nothing.- Parameters:
textRenderingMatrix- the current text rendering matrix, Trmfont- the current fontcode- internal PDF character code for the glyphdisplacement- the displacement (i.e. advance) of the glyph in text space- Throws:
java.io.IOException- if the glyph cannot be processed
-
showFontGlyph
protected void showFontGlyph(Matrix textRenderingMatrix, PDFont font, int code, Vector displacement) throws java.io.IOException
Called when a glyph is to be processed. This method is intended for overriding in subclasses, the default implementation does nothing.- Parameters:
textRenderingMatrix- the current text rendering matrix, Trmfont- the current fontcode- internal PDF character code for the glyphdisplacement- the displacement (i.e. advance) of the glyph in text space- Throws:
java.io.IOException- if the glyph cannot be processed
-
showType3Glyph
protected void showType3Glyph(Matrix textRenderingMatrix, PDType3Font font, int code, Vector displacement) throws java.io.IOException
Called when a glyph is to be processed. This method is intended for overriding in subclasses, the default implementation does nothing.- Parameters:
textRenderingMatrix- the current text rendering matrix, Trmfont- the current fontcode- internal PDF character code for the glyphdisplacement- the displacement (i.e. advance) of the glyph in text space- Throws:
java.io.IOException- if the glyph cannot be processed
-
beginMarkedContentSequence
public void beginMarkedContentSequence(COSName tag, COSDictionary properties)
Called when a marked content group begins- Parameters:
tag- indicates the role or significance of the sequenceproperties- optional properties
-
endMarkedContentSequence
public void endMarkedContentSequence()
Called when a marked content group ends
-
processOperator
public void processOperator(java.lang.String operation, java.util.List<COSBase> arguments) throws java.io.IOExceptionThis is used to handle an operation.- Parameters:
operation- The operation to perform.arguments- The list of arguments.- Throws:
java.io.IOException- If there is an error processing the operation.
-
processOperator
protected void processOperator(Operator operator, java.util.List<COSBase> operands) throws java.io.IOException
This is used to handle an operation.- Parameters:
operator- The operation to perform.operands- The list of arguments.- Throws:
java.io.IOException- If there is an error processing the operation.
-
unsupportedOperator
protected void unsupportedOperator(Operator operator, java.util.List<COSBase> operands) throws java.io.IOException
Called when an unsupported operator is encountered.- Parameters:
operator- The unknown operator.operands- The list of operands.- Throws:
java.io.IOException- if there is an error processing the unsupported operator
-
operatorException
protected void operatorException(Operator operator, java.util.List<COSBase> operands, java.io.IOException exception) throws java.io.IOException
Called when an exception is thrown by an operator.- Parameters:
operator- The unknown operator.operands- The list of operands.exception- the exception which occurred when processing the operator- Throws:
java.io.IOException- if there is an error processing the operator exception
-
saveGraphicsState
public void saveGraphicsState()
Pushes the current graphics state to the stack.
-
restoreGraphicsState
public void restoreGraphicsState()
Pops the current graphics state from the stack.
-
saveGraphicsStack
protected final java.util.Deque<PDGraphicsState> saveGraphicsStack()
Saves the entire graphics stack.- Returns:
- the saved graphics state stack.
-
restoreGraphicsStack
protected final void restoreGraphicsStack(java.util.Deque<PDGraphicsState> snapshot)
Restores the entire graphics stack.- Parameters:
snapshot- the graphics state to be restored
-
getGraphicsStackSize
public int getGraphicsStackSize()
- Returns:
- Returns the size of the graphicsStack.
-
getGraphicsState
public PDGraphicsState getGraphicsState()
- Returns:
- Returns the graphicsState.
-
getTextLineMatrix
public Matrix getTextLineMatrix()
- Returns:
- Returns the textLineMatrix.
-
setTextLineMatrix
public void setTextLineMatrix(Matrix value)
- Parameters:
value- The textLineMatrix to set.
-
getTextMatrix
public Matrix getTextMatrix()
- Returns:
- Returns the textMatrix.
-
setTextMatrix
public void setTextMatrix(Matrix value)
- Parameters:
value- The textMatrix to set.
-
setLineDashPattern
public void setLineDashPattern(COSArray array, int phase)
- Parameters:
array- dash arrayphase- dash phase
-
getResources
public PDResources getResources()
- Returns:
- the stream' resources. This is mainly to be used by the
OperatorProcessorclasses.
-
getCurrentPage
public PDPage getCurrentPage()
Returns the current page.- Returns:
- the current page
-
getInitialMatrix
public Matrix getInitialMatrix()
Gets the stream's initial matrix.- Returns:
- the initial matrix
-
transformedPoint
public java.awt.geom.Point2D.Float transformedPoint(float x, float y)Transforms a point using the CTM.- Parameters:
x- the x-coordinate of the point to be transformedy- the y-coordinate of the point to be transformed- Returns:
- the transformed point
-
transformWidth
protected float transformWidth(float width)
Transforms a width using the CTM.- Parameters:
width- the width to be transformed- Returns:
- the transformed width
-
getLevel
public int getLevel()
Get the current level. This can be used to decide whether a recursion has done too deep and an operation should be skipped to avoid a stack overflow.- Returns:
- the current level.
-
increaseLevel
public void increaseLevel()
Increase the level. Call this before running a potentially recursive operation.
-
decreaseLevel
public void decreaseLevel()
Decrease the level. Call this after running a potentially recursive operation. A log message is shown if the level is below 0. This can happen if the level is not decreased after an operation is done, e.g. by using a "finally" block.
-
isShouldProcessColorOperators
public boolean isShouldProcessColorOperators()
Tells whether color operators should be processed. To be used in some OperatorProcessor classes.- Returns:
- true if color operators should be processed, false if not, e.g. in type3 charprocs with d1 or in uncolored tiling patterns.
-
markedContentPoint
public void markedContentPoint(COSName tag, COSDictionary properties)
Handles MP and DP operators.- Parameters:
tag- indicates the role or significance of the sequenceproperties- optional properties
-
-