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* Licensed to the Apache Software Foundation (ASF) under one
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* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
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*
* http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.pdfbox.preflight.xobject;
import static org.apache.pdfbox.preflight.PreflightConfiguration.RESOURCES_PROCESS;
import static org.apache.pdfbox.preflight.PreflightConstants.ERROR_GRAPHIC_INVALID_BBOX;
import static org.apache.pdfbox.preflight.PreflightConstants.ERROR_GRAPHIC_MISSING_FIELD;
import static org.apache.pdfbox.preflight.PreflightConstants.ERROR_GRAPHIC_TRANSPARENCY_GROUP;
import static org.apache.pdfbox.preflight.PreflightConstants.ERROR_GRAPHIC_UNEXPECTED_KEY;
import static org.apache.pdfbox.preflight.PreflightConstants.ERROR_GRAPHIC_UNEXPECTED_VALUE_FOR_KEY;
import static org.apache.pdfbox.preflight.PreflightConstants.XOBJECT_DICTIONARY_KEY_GROUP;
import static org.apache.pdfbox.preflight.PreflightConstants.XOBJECT_DICTIONARY_VALUE_S_TRANSPARENCY;
import org.apache.pdfbox.cos.COSBase;
import org.apache.pdfbox.cos.COSDictionary;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.PDResources;
import org.apache.pdfbox.pdmodel.graphics.form.PDFormXObject;
import org.apache.pdfbox.preflight.PreflightConstants;
import org.apache.pdfbox.preflight.PreflightContext;
import org.apache.pdfbox.preflight.PreflightPath;
import org.apache.pdfbox.preflight.ValidationResult.ValidationError;
import org.apache.pdfbox.preflight.content.PreflightContentStream;
import org.apache.pdfbox.preflight.exception.ValidationException;
import org.apache.pdfbox.preflight.utils.COSUtils;
import org.apache.pdfbox.preflight.utils.ContextHelper;
/**
* This class validates XObject with the Form subtype.
*/
public class XObjFormValidator extends AbstractXObjValidator
{
/**
* High level object which represents the XObjectForm
*/
PDFormXObject pdXObj = null;
public XObjFormValidator(PreflightContext context, PDFormXObject xobj)
{
super(context, xobj.getCOSStream());
this.pdXObj = xobj;
}
/*
* (non-Javadoc)
*
* @see net.awl.edoc.pdfa.validation.graphics.AbstractXObjValidator#validate()
*/
@Override
public void validate() throws ValidationException
{
super.validate();
checkGroup();
checkSubtype2Value();
validateXObjectResources();
validateXObjectContent();
}
/*
* (non-Javadoc)
*
* @seenet.awl.edoc.pdfa.validation.graphics.AbstractXObjValidator# checkMandatoryFields(java.util.List)
*/
@Override
protected void checkMandatoryFields()
{
boolean lastMod = this.xobject.getItem(COSName.LAST_MODIFIED) != null;
boolean pieceInfo = this.xobject.getItem("PieceInfo") != null;
// type and subtype checked before to create the Validator.
if (lastMod ^ pieceInfo)
{
context.addValidationError(new ValidationError(ERROR_GRAPHIC_MISSING_FIELD));
return;
}
COSBase bbBase = this.xobject.getItem(COSName.BBOX);
// ---- BBox is an Array (Rectangle)
if (bbBase == null || !COSUtils.isArray(bbBase, cosDocument))
{
context.addValidationError(new ValidationError(ERROR_GRAPHIC_INVALID_BBOX));
return;
}
}
/**
* An Form XObject is a ContentStream. This method method uses an instance of ContentStreamWrapper to check the
* Stream of this Form XObject.
*/
protected void validateXObjectContent() throws ValidationException
{
PreflightPath vPath = context.getValidationPath();
PreflightContentStream csWrapper = new PreflightContentStream(context, vPath.getClosestPathElement(PDPage.class));
csWrapper.validXObjContentStream(pdXObj);
}
/**
* A Form XObject may contain a Group object (Key =" Group"). If a Group object is present, this method checks if
* the S entry is present and if its value is different from "Transparency".
*
*/
protected void checkGroup()
{
COSBase baseGroup = this.xobject.getItem(XOBJECT_DICTIONARY_KEY_GROUP);
COSDictionary groupDictionary = COSUtils.getAsDictionary(baseGroup, cosDocument);
if (groupDictionary != null)
{
if (!XOBJECT_DICTIONARY_KEY_GROUP.equals(groupDictionary.getNameAsString(COSName.TYPE)))
{
context.addValidationError(new ValidationError(PreflightConstants.ERROR_GRAPHIC_MISSING_FIELD, "The Group dictionary hasn't Group as Type value"));
}
else
{
String sVal = groupDictionary.getNameAsString(COSName.S);
if (sVal == null || XOBJECT_DICTIONARY_VALUE_S_TRANSPARENCY.equals(sVal))
{
context.addValidationError(new ValidationError(ERROR_GRAPHIC_TRANSPARENCY_GROUP, "Group has a transparency S entry or the S entry is null ["+xobject.toString()+"]"));
return;
}
}
}
}
/**
* Check if there are no PS entry in the Form XObject dictionary
*/
protected void checkPS()
{
// 6.2.4 and 6.2.5 no PS
if (this.xobject.getItem(COSName.getPDFName("PS")) != null)
{
context.addValidationError(new ValidationError(ERROR_GRAPHIC_UNEXPECTED_KEY, "Unexpected 'PS' Key"));
return;
}
}
/**
* Check the SUbtype2 entry according to the §6.2.5 of the ISO 190005-1:2005 specification.
*/
protected void checkSubtype2Value()
{
// 6.2.5 if Subtype2, value not PS
if (this.xobject.getItem(COSName.getPDFName("Subtype2")) != null)
{
if ("PS".equals(this.xobject.getNameAsString("Subtype2")))
{
context.addValidationError(new ValidationError(ERROR_GRAPHIC_UNEXPECTED_VALUE_FOR_KEY,
"Unexpected 'PS' value for 'Subtype2' Key"));
return;
}
}
}
protected void validateXObjectResources() throws ValidationException
{
PDResources resources = this.pdXObj.getResources();
if (resources != null)
{
ContextHelper.validateElement(context, resources, RESOURCES_PROCESS);
}
}
}