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package org.apache.padaf.preflight.helpers;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.padaf.preflight.DocumentHandler;
import org.apache.padaf.preflight.ValidationException;
import org.apache.padaf.preflight.ValidatorConfig;
import org.apache.padaf.preflight.ValidationResult.ValidationError;
import org.apache.padaf.preflight.actions.AbstractActionManager;
import org.apache.padaf.preflight.annotation.AnnotationValidator;
import org.apache.padaf.preflight.contentstream.ContentStreamWrapper;
import org.apache.padaf.preflight.graphics.ExtGStateContainer;
import org.apache.padaf.preflight.graphics.ShadingPattern;
import org.apache.pdfbox.cos.COSDictionary;
import org.apache.pdfbox.cos.COSDocument;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.pdmodel.PDDocumentCatalog;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.PDResources;
import org.apache.pdfbox.pdmodel.interactive.annotation.PDAnnotation;
public class PagesValidationHelper extends AbstractValidationHelper {
public PagesValidationHelper(ValidatorConfig cfg)
throws ValidationException {
super(cfg);
}
/*
* (non-Javadoc)
*
* @see
* net.awl.edoc.pdfa.validation.helpers.AbstractValidationHelper#innerValidate
* (net.awl.edoc.pdfa.validation.DocumentHandler)
*/
@Override
public List<ValidationError> innerValidate(DocumentHandler handler)
throws ValidationException {
List<ValidationError> result = new ArrayList<ValidationError>(0);
PDDocumentCatalog catalog = handler.getDocument().getDocumentCatalog();
if (catalog != null) {
// ---- PDFBox provides a method which returns all pages in a List.
// Currently, it is useless to explore the Pages hierarchy.
List<?> pages = catalog.getAllPages();
for (int i = 0; i < pages.size(); ++i) {
if (!validatePage((PDPage) pages.get(i), handler, result)) {
return result;
}
}
} else {
throw new ValidationException(
"There are no Catalog entry in the Document.");
}
return result;
}
/**
* This method checks the given page. Only a part of element contained by the
* page will be checked, like :
* <UL>
* <li>Presence of mandatory elements
* <li>The page content when it is possible (ex : text area)
* <li>The Additional Actions are authorized
* <li>etc...
* </UL>
*
* @param page
* @param handler
* @param result
* @return
*/
protected boolean validatePage(PDPage page, DocumentHandler handler,
List<ValidationError> result) throws ValidationException {
boolean isValid = validateActions(page, handler, result);
isValid = isValid && validateAnnotation(page, handler, result);
isValid = isValid && validateTransparency(page, handler, result);
isValid = isValid && validateContent(page, handler, result);
isValid = isValid && validateShadingPattern(page, handler, result);
return isValid;
}
/**
* This method checks additional actions contained in the given Page object.
*
* @param page
* @param handler
* @param result
* @return
* @throws ValidationException
*/
protected boolean validateActions(PDPage page, DocumentHandler handler,
List<ValidationError> result) throws ValidationException {
// ---- get AA (additional actions) entry if it is present
List<AbstractActionManager> lActions = this.actionFact.getActions(page
.getCOSDictionary(), handler.getDocument().getDocument());
for (AbstractActionManager action : lActions) {
if (!action.valid(true, result)) {
return false;
}
}
return true;
}
/**
* This method check the ExtGState entry of the resource dictionary.
*
* @param page
* @param handler
* @param result
* @return
* @throws ValidationException
*/
protected boolean validateTransparency(PDPage page, DocumentHandler handler,
List<ValidationError> result) throws ValidationException {
PDResources resources = page.getResources();
COSDocument cDoc = handler.getDocument().getDocument();
ExtGStateContainer extGStates = new ExtGStateContainer(resources
.getCOSDictionary(), cDoc);
return extGStates.validateTransparencyRules(result);
// ---- Even if a Group entry is possible in the Page dictionary, No
// restrictions are defined by PDF/A
}
/**
* This method check the Shading entry of the resource dictionary if exists.
*
* @param page
* @param handler
* @param result
* @return
* @throws ValidationException
*/
protected boolean validateShadingPattern(PDPage page,
DocumentHandler handler, List<ValidationError> result)
throws ValidationException {
PDResources resources = page.getResources();
COSDictionary shadings = (COSDictionary) resources.getCOSDictionary()
.getDictionaryObject(PATTERN_KEY_SHADING);
boolean res = true;
if (shadings != null) {
for (Object key : shadings.keySet()) {
COSDictionary aShading = (COSDictionary) shadings
.getDictionaryObject((COSName) key);
ShadingPattern sp = new ShadingPattern(handler, aShading);
List<ValidationError> lErrors = sp.validate();
if (lErrors != null && !lErrors.isEmpty()) {
result.addAll(lErrors);
res = false;
}
}
}
return res;
}
/**
*
* @param page
* @param handler
* @param result
* @return
* @throws ValidationException
*/
protected boolean validateContent(PDPage page, DocumentHandler handler,
List<ValidationError> result) throws ValidationException {
ContentStreamWrapper csWrapper = new ContentStreamWrapper(handler);
List<ValidationError> csParseErrors = csWrapper.validPageContentStream(page);
if (csParseErrors == null || csParseErrors.isEmpty()) {
return true;
}
result.addAll(csParseErrors);
return false;
}
/**
*
* @param page
* @param handler
* @param result
* @return
* @throws ValidationException
*/
protected boolean validateAnnotation(PDPage page, DocumentHandler handler,
List<ValidationError> result) throws ValidationException {
try {
List<?> lAnnots = page.getAnnotations();
for (Object object : lAnnots) {
if (object instanceof PDAnnotation) {
COSDictionary cosAnnot = ((PDAnnotation) object).getDictionary();
AnnotationValidator validator = this.annotFact.getAnnotationValidator(cosAnnot, handler, result);
if (validator != null) {
return validator.validate(result);
}
}
}
} catch (IOException e) {
throw new ValidationException("Unable to access Annotation", e);
}
// --- No annotations, validation OK
return true;
}
}