com.itextpdf.pdfa.checker

Class PdfAChecker

java.lang.Object

com.itextpdf.pdfa.checker.PdfAChecker

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

PdfA1Checker

public abstract class PdfAChecker
extends Object
implements Serializable

An abstract class that will run through all necessary checks defined in the different PDF/A standards and levels. A number of common checks are executed in this class, while standard-dependent specifications are implemented in the available subclasses. The standard that is followed is the series of ISO 19005 specifications, currently generations 1 through 3. The ZUGFeRD standard is derived from ISO 19005-3. While it is possible to subclass this method and implement its abstract methods in client code, this is not encouraged and will have little effect. It is not possible to plug custom implementations into iText, because iText should always refuse to create non-compliant PDF/A, which would be possible with client code implementations. Any future generations of the PDF/A standard and its derivates will get their own implementation in the iText 7 - pdfa project.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected Set<PdfObject>	checkedObjects Contains some objects that are already checked.
protected Map<PdfObject,PdfColorSpace>	checkedObjectsColorspace
protected boolean	cmykIsUsed
protected PdfAConformanceLevel	conformanceLevel
protected boolean	grayIsUsed
protected int	gsStackDepth
static String	ICC_COLOR_SPACE_CMYK The Cyan-Magenta-Yellow-Key (black) color profile as defined by the International Color Consortium.
static String	ICC_COLOR_SPACE_GRAY The Grayscale color profile as defined by the International Color Consortium.
static String	ICC_COLOR_SPACE_RGB The Red-Green-Blue color profile as defined by the International Color Consortium.
static String	ICC_DEVICE_CLASS_MONITOR_PROFILE The Monitor device class
static String	ICC_DEVICE_CLASS_OUTPUT_PROFILE The Output device class
protected Logger	LOGGER Deprecated. Use slf4j logging instead.
static int	maxGsStackDepth The maximum Graphics State stack depth in PDF/A documents, i.e.
protected String	pdfAOutputIntentColorSpace
protected boolean	rgbIsUsed

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	PdfAChecker(PdfAConformanceLevel conformanceLevel)

Method Summary

Modifier and Type	Method and Description
protected abstract void	checkAction(PdfDictionary action)
protected abstract void	checkAnnotation(PdfDictionary annotDic)
abstract void	checkCanvasStack(char stackOperation) This method checks compliance with the graphics state architectural limitation, explained by maxGsStackDepth.
protected abstract void	checkCatalogValidEntries(PdfDictionary catalogDict)
abstract void	checkColor(Color color, PdfDictionary currentColorSpaces, Boolean fill) This method checks compliance with the color restrictions imposed by the available color spaces in the document.
abstract void	checkColorSpace(PdfColorSpace colorSpace, PdfDictionary currentColorSpaces, boolean checkAlternate, Boolean fill) This method performs a range of checks on the given color space, depending on the type and properties of that color space.
protected abstract void	checkColorsUsages()
void	checkDocument(PdfCatalog catalog) This method checks a number of document-wide requirements of the PDF/A standard.
abstract void	checkExtGState(CanvasGraphicsState extGState) Performs a number of checks on the graphics state, among others ISO 19005-1 section 6.2.8 and 6.4 and ISO 19005-2 section 6.2.5 and 6.2.10.
protected abstract void	checkFileSpec(PdfDictionary fileSpec)
protected static boolean	checkFlag(int flags, int flag)
void	checkFont(PdfFont pdfFont) Performs a number of checks on the font.
protected abstract void	checkForm(PdfDictionary form)
protected abstract void	checkFormXObject(PdfStream form)
protected abstract void	checkImage(PdfStream image, PdfDictionary currentColorSpaces)
abstract void	checkInlineImage(PdfStream inlineImage, PdfDictionary currentColorSpaces) This method checks compliance with the inline image restrictions in the PDF/A specs, specifically filter parameters.
protected abstract void	checkLogicalStructure(PdfDictionary catalog)
protected abstract void	checkMetaData(PdfDictionary catalog)
protected void	checkNonSymbolicTrueTypeFont(PdfTrueTypeFont trueTypeFont)
protected abstract void	checkOutputIntents(PdfDictionary catalog)
protected abstract void	checkPageObject(PdfDictionary page, PdfDictionary pageResources)
protected abstract void	checkPageSize(PdfDictionary page)
protected abstract void	checkPdfNumber(PdfNumber number)
void	checkPdfObject(PdfObject obj) This method checks the requirements that must be fulfilled by a COS object in a PDF/A document.
protected abstract void	checkPdfStream(PdfStream stream)
protected abstract void	checkPdfString(PdfString string)
abstract void	checkRenderingIntent(PdfName intent) Checks whether the rendering intent of the document is within the allowed range of intents.
protected void	checkResources(PdfDictionary resources)
protected void	checkResourcesOfAppearanceStreams(PdfDictionary appearanceStreamsDict)
void	checkSinglePage(PdfPage page) This method checks all requirements that must be fulfilled by a page in a PDF/A document.
protected static boolean	checkStructure(PdfAConformanceLevel conformanceLevel)
protected void	checkSymbolicTrueTypeFont(PdfTrueTypeFont trueTypeFont)
void	checkTagStructureElement(PdfObject obj) This method checks compliance of the tag structure elements, such as struct elements or parent tree entries.
protected abstract void	checkTrailer(PdfDictionary trailer)
protected abstract Set<PdfName>	getAllowedNamedActions()
PdfAConformanceLevel	getConformanceLevel() Gets the PdfAConformanceLevel for this file.
protected abstract Set<PdfName>	getForbiddenActions()
protected boolean	isAlreadyChecked(PdfDictionary dictionary)
boolean	objectIsChecked(PdfObject object) Remembers which objects have already been checked, in order to avoid redundant checks.

Methods inherited from class java.lang.Object

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

Field Detail

LOGGER

@Deprecated
protected transient Logger LOGGER

Deprecated. Use slf4j logging instead.

ICC_COLOR_SPACE_RGB

public static final String ICC_COLOR_SPACE_RGB

The Red-Green-Blue color profile as defined by the International Color Consortium.

See Also:

Constant Field Values

ICC_COLOR_SPACE_CMYK

public static final String ICC_COLOR_SPACE_CMYK

The Cyan-Magenta-Yellow-Key (black) color profile as defined by the International Color Consortium.

See Also:

Constant Field Values

ICC_COLOR_SPACE_GRAY

public static final String ICC_COLOR_SPACE_GRAY

The Grayscale color profile as defined by the International Color Consortium.

See Also:

Constant Field Values

ICC_DEVICE_CLASS_OUTPUT_PROFILE

public static final String ICC_DEVICE_CLASS_OUTPUT_PROFILE

The Output device class

See Also:

Constant Field Values

ICC_DEVICE_CLASS_MONITOR_PROFILE

public static final String ICC_DEVICE_CLASS_MONITOR_PROFILE

The Monitor device class

See Also:

Constant Field Values

maxGsStackDepth

public static final int maxGsStackDepth

The maximum Graphics State stack depth in PDF/A documents, i.e. the maximum number of graphics state operators with code q that may be opened (i.e. not yet closed by a corresponding Q) at any point in a content stream sequence. Defined as 28 by PDF/A-1 section 6.1.12, by referring to the PDF spec Appendix C table 1 "architectural limits".

See Also:

Constant Field Values

conformanceLevel

protected PdfAConformanceLevel conformanceLevel

pdfAOutputIntentColorSpace

protected String pdfAOutputIntentColorSpace

gsStackDepth

protected int gsStackDepth

rgbIsUsed

protected boolean rgbIsUsed

cmykIsUsed

protected boolean cmykIsUsed

grayIsUsed

protected boolean grayIsUsed

checkedObjects

protected Set<PdfObject> checkedObjects

Contains some objects that are already checked. NOTE: Not all objects that were checked are stored in that set. This set is used for avoiding double checks for actions, xObjects and page objects; and for letting those objects to be manually flushed. Use this mechanism carefully: objects that are able to be changed (or at least if object's properties that shall be checked are able to be changed) shouldn't be marked as checked if they are not to be flushed immediately.

checkedObjectsColorspace

protected Map<PdfObject,PdfColorSpace> checkedObjectsColorspace

Constructor Detail

PdfAChecker

protected PdfAChecker(PdfAConformanceLevel conformanceLevel)

Method Detail

checkDocument

public void checkDocument(PdfCatalog catalog)

This method checks a number of document-wide requirements of the PDF/A standard. The algorithms of some of these checks vary with the PDF/A level and thus are implemented in subclasses; others are implemented as private methods in this class.

Parameters:

catalog -

checkSinglePage

public void checkSinglePage(PdfPage page)

This method checks all requirements that must be fulfilled by a page in a PDF/A document.

Parameters:

page - the page that must be checked

checkPdfObject

public void checkPdfObject(PdfObject obj)

This method checks the requirements that must be fulfilled by a COS object in a PDF/A document.

Parameters:

obj - the COS object that must be checked

getConformanceLevel

public PdfAConformanceLevel getConformanceLevel()

Gets the PdfAConformanceLevel for this file.

Returns:

the defined conformance level for this document.

objectIsChecked

public boolean objectIsChecked(PdfObject object)

Remembers which objects have already been checked, in order to avoid redundant checks.

Parameters:

object - the object to check

Returns:

whether or not the object has already been checked

checkTagStructureElement

public void checkTagStructureElement(PdfObject obj)

This method checks compliance of the tag structure elements, such as struct elements or parent tree entries.

Parameters:

obj - an object that represents tag structure element.

checkCanvasStack

public abstract void checkCanvasStack(char stackOperation)

This method checks compliance with the graphics state architectural limitation, explained by maxGsStackDepth.

Parameters:

stackOperation - the operation to check the graphics state counter for

checkInlineImage

public abstract void checkInlineImage(PdfStream inlineImage,
                                      PdfDictionary currentColorSpaces)

This method checks compliance with the inline image restrictions in the PDF/A specs, specifically filter parameters.

Parameters:

inlineImage - a PdfStream containing the inline image

currentColorSpaces - a PdfDictionary containing the color spaces used in the document

checkColor

public abstract void checkColor(Color color,
                                PdfDictionary currentColorSpaces,
                                Boolean fill)

This method checks compliance with the color restrictions imposed by the available color spaces in the document.

Parameters:

color - the color to check

currentColorSpaces - a PdfDictionary containing the color spaces used in the document

fill - whether the color is used for fill or stroke operations

checkColorSpace

public abstract void checkColorSpace(PdfColorSpace colorSpace,
                                     PdfDictionary currentColorSpaces,
                                     boolean checkAlternate,
                                     Boolean fill)

This method performs a range of checks on the given color space, depending on the type and properties of that color space.

Parameters:

colorSpace - the color space to check

currentColorSpaces - a PdfDictionary containing the color spaces used in the document

checkAlternate - whether or not to also check the parent color space

fill - whether the color space is used for fill or stroke operations

checkRenderingIntent

public abstract void checkRenderingIntent(PdfName intent)

Checks whether the rendering intent of the document is within the allowed range of intents. This is defined in ISO 19005-1 section 6.2.9, and unchanged in newer generations of the PDF/A specification.

Parameters:

intent - the intent to be analyzed

checkExtGState

public abstract void checkExtGState(CanvasGraphicsState extGState)

Performs a number of checks on the graphics state, among others ISO 19005-1 section 6.2.8 and 6.4 and ISO 19005-2 section 6.2.5 and 6.2.10.

Parameters:

extGState - the graphics state to be checked

checkFont

public void checkFont(PdfFont pdfFont)

Performs a number of checks on the font. See ISO 19005-1 section 6.3, ISO 19005-2 and ISO 19005-3 section 6.2.11. Be aware that not all constraints defined in the ISO are checked in this method, for most of them we consider that iText always creates valid fonts.

Parameters:

pdfFont - font to be checked

getForbiddenActions

protected abstract Set<PdfName> getForbiddenActions()

getAllowedNamedActions

protected abstract Set<PdfName> getAllowedNamedActions()

checkAction

protected abstract void checkAction(PdfDictionary action)

checkAnnotation

protected abstract void checkAnnotation(PdfDictionary annotDic)

checkCatalogValidEntries

protected abstract void checkCatalogValidEntries(PdfDictionary catalogDict)

checkColorsUsages

protected abstract void checkColorsUsages()

checkImage

protected abstract void checkImage(PdfStream image,
                                   PdfDictionary currentColorSpaces)

checkFileSpec

protected abstract void checkFileSpec(PdfDictionary fileSpec)

checkForm

protected abstract void checkForm(PdfDictionary form)

checkFormXObject

protected abstract void checkFormXObject(PdfStream form)

checkLogicalStructure

protected abstract void checkLogicalStructure(PdfDictionary catalog)

checkMetaData

protected abstract void checkMetaData(PdfDictionary catalog)

checkNonSymbolicTrueTypeFont

protected void checkNonSymbolicTrueTypeFont(PdfTrueTypeFont trueTypeFont)

checkOutputIntents

protected abstract void checkOutputIntents(PdfDictionary catalog)

checkPageObject

protected abstract void checkPageObject(PdfDictionary page,
                                        PdfDictionary pageResources)

checkPageSize

protected abstract void checkPageSize(PdfDictionary page)

checkPdfNumber

protected abstract void checkPdfNumber(PdfNumber number)

checkPdfStream

protected abstract void checkPdfStream(PdfStream stream)

checkPdfString

protected abstract void checkPdfString(PdfString string)

checkSymbolicTrueTypeFont

protected void checkSymbolicTrueTypeFont(PdfTrueTypeFont trueTypeFont)

checkTrailer

protected abstract void checkTrailer(PdfDictionary trailer)

checkResources

protected void checkResources(PdfDictionary resources)

checkFlag

protected static boolean checkFlag(int flags,
                                   int flag)

checkStructure

protected static boolean checkStructure(PdfAConformanceLevel conformanceLevel)

isAlreadyChecked

protected boolean isAlreadyChecked(PdfDictionary dictionary)

checkResourcesOfAppearanceStreams

protected void checkResourcesOfAppearanceStreams(PdfDictionary appearanceStreamsDict)