PDAcroForm.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information 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 with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.pdfbox.pdmodel.interactive.form;
import java.awt.geom.GeneralPath;
import java.awt.geom.Rectangle2D;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.pdfbox.cos.COSArray;
import org.apache.pdfbox.cos.COSBase;
import org.apache.pdfbox.cos.COSDictionary;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.PDPageContentStream;
import org.apache.pdfbox.pdmodel.PDPageContentStream.AppendMode;
import org.apache.pdfbox.pdmodel.PDResources;
import org.apache.pdfbox.pdmodel.common.COSArrayList;
import org.apache.pdfbox.pdmodel.common.COSObjectable;
import org.apache.pdfbox.pdmodel.common.PDRectangle;
import org.apache.pdfbox.pdmodel.fdf.FDFCatalog;
import org.apache.pdfbox.pdmodel.fdf.FDFDictionary;
import org.apache.pdfbox.pdmodel.fdf.FDFDocument;
import org.apache.pdfbox.pdmodel.fdf.FDFField;
import org.apache.pdfbox.pdmodel.graphics.form.PDFormXObject;
import org.apache.pdfbox.pdmodel.interactive.annotation.PDAnnotation;
import org.apache.pdfbox.pdmodel.interactive.annotation.PDAnnotationWidget;
import org.apache.pdfbox.pdmodel.interactive.annotation.PDAppearanceStream;
import org.apache.pdfbox.util.Matrix;
/**
* An interactive form, also known as an AcroForm.
*
* @author Ben Litchfield
*/
public final class PDAcroForm implements COSObjectable
{
private static final Log LOG = LogFactory.getLog(PDAcroForm.class);
private static final int FLAG_SIGNATURES_EXIST = 1;
private static final int FLAG_APPEND_ONLY = 1 << 1;
private final PDDocument document;
private final COSDictionary dictionary;
private Map<String, PDField> fieldCache;
private ScriptingHandler scriptingHandler;
/**
* Constructor.
*
* @param doc The document that this form is part of.
*/
public PDAcroForm(PDDocument doc)
{
document = doc;
dictionary = new COSDictionary();
dictionary.setItem(COSName.FIELDS, new COSArray());
}
/**
* Constructor.
*
* @param doc The document that this form is part of.
* @param form The existing acroForm.
*/
public PDAcroForm(PDDocument doc, COSDictionary form)
{
document = doc;
dictionary = form;
}
/**
* This will get the document associated with this form.
*
* @return The PDF document.
*/
PDDocument getDocument()
{
return document;
}
@Override
public COSDictionary getCOSObject()
{
return dictionary;
}
/**
* This method will import an entire FDF document into the PDF document
* that this acroform is part of.
*
* @param fdf The FDF document to import.
*
* @throws IOException If there is an error doing the import.
*/
public void importFDF(FDFDocument fdf) throws IOException
{
List<FDFField> fields = fdf.getCatalog().getFDF().getFields();
if (fields != null)
{
for (FDFField field : fields)
{
FDFField fdfField = field;
PDField docField = getField(fdfField.getPartialFieldName());
if (docField != null)
{
docField.importFDF(fdfField);
}
}
}
}
/**
* This will export all FDF form data.
*
* @return An FDF document used to export the document.
* @throws IOException If there is an error when exporting the document.
*/
public FDFDocument exportFDF() throws IOException
{
FDFDocument fdf = new FDFDocument();
FDFCatalog catalog = fdf.getCatalog();
FDFDictionary fdfDict = new FDFDictionary();
catalog.setFDF(fdfDict);
List<FDFField> fdfFields = new ArrayList<>();
List<PDField> fields = getFields();
for (PDField field : fields)
{
fdfFields.add(field.exportFDF());
}
fdfDict.setID(document.getDocument().getDocumentID());
if (!fdfFields.isEmpty())
{
fdfDict.setFields(fdfFields);
}
return fdf;
}
/**
* This will flatten all form fields.
*
* <p>Flattening a form field will take the current appearance and make that part
* of the pages content stream. All form fields and annotations associated are removed.</p>
*
* <p>Invisible and hidden fields will be skipped and will not become part of the
* page content stream</p>
*
* <p>The appearances for the form fields widgets will <strong>not</strong> be generated<p>
*
* @throws IOException
*/
public void flatten() throws IOException
{
// for dynamic XFA forms there is no flatten as this would mean to do a rendering
// from the XFA content into a static PDF.
if (xfaIsDynamic())
{
LOG.warn("Flatten for a dynamix XFA form is not supported");
return;
}
List<PDField> fields = new ArrayList<>();
for (PDField field: getFieldTree())
{
fields.add(field);
}
flatten(fields, false);
}
/**
* This will flatten the specified form fields.
*
* <p>Flattening a form field will take the current appearance and make that part
* of the pages content stream. All form fields and annotations associated are removed.</p>
*
* <p>Invisible and hidden fields will be skipped and will not become part of the
* page content stream</p>
*
* @param fields
* @param refreshAppearances if set to true the appearances for the form field widgets will be updated
* @throws IOException
*/
public void flatten(List<PDField> fields, boolean refreshAppearances) throws IOException
{
// Nothing to flatten if there are no fields provided
if (fields.isEmpty())
{
return;
}
if (!refreshAppearances && getNeedAppearances())
{
LOG.warn("acroForm.getNeedAppearances() returns true, " +
"visual field appearances may not have been set");
LOG.warn("call acroForm.refreshAppearances() or " +
"use the flatten() method with refreshAppearances parameter");
}
// for dynamic XFA forms there is no flatten as this would mean to do a rendering
// from the XFA content into a static PDF.
if (xfaIsDynamic())
{
LOG.warn("Flatten for a dynamix XFA form is not supported");
return;
}
// refresh the appearances if set
if (refreshAppearances)
{
refreshAppearances(fields);
}
Map<COSDictionary,Set<COSDictionary>> pagesWidgetsMap = buildPagesWidgetsMap(fields);
// preserve all non widget annotations
for (PDPage page : document.getPages())
{
Set<COSDictionary> widgetsForPageMap = pagesWidgetsMap.get(page.getCOSObject());
// indicates if the original content stream
// has been wrapped in a q...Q pair.
boolean isContentStreamWrapped = false;
List<PDAnnotation> annotations = new ArrayList<>();
for (PDAnnotation annotation: page.getAnnotations())
{
if (widgetsForPageMap == null || !widgetsForPageMap.contains(annotation.getCOSObject()))
{
annotations.add(annotation);
}
else if (isVisibleAnnotation(annotation))
{
try (PDPageContentStream contentStream = new PDPageContentStream(
document, page, AppendMode.APPEND, true, !isContentStreamWrapped))
{
isContentStreamWrapped = true;
PDAppearanceStream appearanceStream = annotation.getNormalAppearanceStream();
PDFormXObject fieldObject = new PDFormXObject(appearanceStream.getCOSObject());
contentStream.saveGraphicsState();
// see https://stackoverflow.com/a/54091766/1729265 for an explanation
// of the steps required
// this will transform the appearance stream form object into the rectangle of the
// annotation bbox and map the coordinate systems
Matrix transformationMatrix = resolveTransformationMatrix(annotation, appearanceStream);
contentStream.transform(transformationMatrix);
contentStream.drawForm(fieldObject);
contentStream.restoreGraphicsState();
}
}
}
page.setAnnotations(annotations);
}
// remove the fields
removeFields(fields);
// remove XFA for hybrid forms
dictionary.removeItem(COSName.XFA);
// remove SigFlags if no signature left
if (this.document.getSignatureDictionaries().isEmpty())
{
this.getCOSObject().removeItem(COSName.SIG_FLAGS);
}
}
private boolean isVisibleAnnotation(PDAnnotation annotation)
{
if (annotation.isInvisible() || annotation.isHidden())
{
return false;
}
PDAppearanceStream normalAppearanceStream = annotation.getNormalAppearanceStream();
if (normalAppearanceStream == null)
{
return false;
}
PDRectangle bbox = normalAppearanceStream.getBBox();
return bbox != null && bbox.getWidth() > 0 && bbox.getHeight() > 0;
}
/**
* Refreshes the appearance streams and appearance dictionaries for
* the widget annotations of all fields.
*
* @throws IOException
*/
public void refreshAppearances() throws IOException
{
for (PDField field : getFieldTree())
{
if (field instanceof PDTerminalField)
{
((PDTerminalField) field).constructAppearances();
}
}
}
/**
* Refreshes the appearance streams and appearance dictionaries for
* the widget annotations of the specified fields.
*
* @param fields
* @throws IOException
*/
public void refreshAppearances(List<PDField> fields) throws IOException
{
for (PDField field : fields)
{
if (field instanceof PDTerminalField)
{
((PDTerminalField) field).constructAppearances();
}
}
}
/**
* This will return all of the documents root fields.
*
* A field might have children that are fields (non-terminal field) or does not
* have children which are fields (terminal fields).
*
* The fields within an AcroForm are organized in a tree structure. The documents root fields
* might either be terminal fields, non-terminal fields or a mixture of both. Non-terminal fields
* mark branches which contents can be retrieved using {@link PDNonTerminalField#getChildren()}.
*
* @return A list of the documents root fields, never null. If there are no fields then this
* method returns an empty list.
*/
public List<PDField> getFields()
{
COSArray cosFields = dictionary.getCOSArray(COSName.FIELDS);
if (cosFields == null)
{
return Collections.emptyList();
}
List<PDField> pdFields = new ArrayList<>();
for (int i = 0; i < cosFields.size(); i++)
{
COSDictionary element = (COSDictionary) cosFields.getObject(i);
if (element != null)
{
PDField field = PDField.fromDictionary(this, element, null);
if (field != null)
{
pdFields.add(field);
}
}
}
return new COSArrayList<>(pdFields, cosFields);
}
/**
* Set the documents root fields.
*
* @param fields The fields that are part of the documents root fields.
*/
public void setFields(List<PDField> fields)
{
dictionary.setItem(COSName.FIELDS, new COSArray(fields));
}
/**
* Returns an iterator which walks all fields in the field tree, in order.
*/
public Iterator<PDField> getFieldIterator()
{
return new PDFieldTree(this).iterator();
}
/**
* Return the field tree representing all form fields
*/
public PDFieldTree getFieldTree()
{
return new PDFieldTree(this);
}
/**
* This will tell this form to cache the fields into a Map structure
* for fast access via the getField method. The default is false. You would
* want this to be false if you were changing the COSDictionary behind the scenes,
* otherwise setting this to true is acceptable.
*
* @param cache A boolean telling if we should cache the fields.
*/
public void setCacheFields(boolean cache)
{
if (cache)
{
fieldCache = new HashMap<>();
for (PDField field : getFieldTree())
{
fieldCache.put(field.getFullyQualifiedName(), field);
}
}
else
{
fieldCache = null;
}
}
/**
* This will tell if this acro form is caching the fields.
*
* @return true if the fields are being cached.
*/
public boolean isCachingFields()
{
return fieldCache != null;
}
/**
* This will get a field by name, possibly using the cache if setCache is true.
*
* @param fullyQualifiedName The name of the field to get.
* @return The field with that name of null if one was not found.
*/
public PDField getField(String fullyQualifiedName)
{
// get the field from the cache if there is one.
if (fieldCache != null)
{
return fieldCache.get(fullyQualifiedName);
}
// get the field from the field tree
for (PDField field : getFieldTree())
{
if (field.getFullyQualifiedName().equals(fullyQualifiedName))
{
return field;
}
}
return null;
}
/**
* Get the default appearance.
*
* @return the DA element of the dictionary object
*/
public String getDefaultAppearance()
{
return dictionary.getString(COSName.DA,"");
}
/**
* Set the default appearance.
*
* @param daValue a string describing the default appearance
*/
public void setDefaultAppearance(String daValue)
{
dictionary.setString(COSName.DA, daValue);
}
/**
* True if the viewing application should construct the appearances of all field widgets.
* The default value is false.
*
* @return the value of NeedAppearances, false if the value isn't set
*/
public boolean getNeedAppearances()
{
return dictionary.getBoolean(COSName.NEED_APPEARANCES, false);
}
/**
* Set the NeedAppearances value. If this is false, PDFBox will create appearances for all field
* widget.
*
* @param value the value for NeedAppearances
*/
public void setNeedAppearances(Boolean value)
{
dictionary.setBoolean(COSName.NEED_APPEARANCES, value);
}
/**
* This will get the default resources for the AcroForm.
*
* @return The default resources or null if there is none.
*/
public PDResources getDefaultResources()
{
COSDictionary dr = dictionary.getCOSDictionary(COSName.DR);
return dr != null ? new PDResources(dr, document.getResourceCache()) : null;
}
/**
* This will set the default resources for the acroform.
*
* @param dr The new default resources.
*/
public void setDefaultResources(PDResources dr)
{
dictionary.setItem(COSName.DR, dr);
}
/**
* This will tell if the AcroForm has XFA content.
*
* @return true if the AcroForm is an XFA form
*/
public boolean hasXFA()
{
return dictionary.containsKey(COSName.XFA);
}
/**
* This will tell if the AcroForm is a dynamic XFA form.
*
* @return true if the AcroForm is a dynamic XFA form
*/
public boolean xfaIsDynamic()
{
return hasXFA() && getFields().isEmpty();
}
/**
* Get the XFA resource, the XFA resource is only used for PDF 1.5+ forms.
*
* @return The xfa resource or null if it does not exist.
*/
public PDXFAResource getXFA()
{
COSBase base = dictionary.getDictionaryObject(COSName.XFA);
return base != null ? new PDXFAResource(base) : null;
}
/**
* Set the XFA resource, this is only used for PDF 1.5+ forms.
*
* @param xfa The xfa resource.
*/
public void setXFA(PDXFAResource xfa)
{
dictionary.setItem(COSName.XFA, xfa);
}
/**
* This will get the document-wide default value for the quadding/justification of variable text
* fields.
* <p>
* 0 - Left(default)<br>
* 1 - Centered<br>
* 2 - Right<br>
* See the QUADDING constants of {@link PDVariableText}.
*
* @return The justification of the variable text fields.
*/
public int getQ()
{
return dictionary.getInt(COSName.Q, 0);
}
/**
* This will set the document-wide default value for the quadding/justification of variable text
* fields. See the QUADDING constants of {@link PDVariableText}.
*
* @param q The justification of the variable text fields.
*/
public void setQ(int q)
{
dictionary.setInt(COSName.Q, q);
}
/**
* Determines if SignaturesExist is set.
*
* @return true if the document contains at least one signature.
*/
public boolean isSignaturesExist()
{
return dictionary.getFlag(COSName.SIG_FLAGS, FLAG_SIGNATURES_EXIST);
}
/**
* Set the SignaturesExist bit.
*
* @param signaturesExist The value for SignaturesExist.
*/
public void setSignaturesExist(boolean signaturesExist)
{
dictionary.setFlag(COSName.SIG_FLAGS, FLAG_SIGNATURES_EXIST, signaturesExist);
}
/**
* Determines if AppendOnly is set.
*
* @return true if the document contains signatures that may be invalidated if the file is saved.
*/
public boolean isAppendOnly()
{
return dictionary.getFlag(COSName.SIG_FLAGS, FLAG_APPEND_ONLY);
}
/**
* Set a handler to support JavaScript actions in the form.
*
* @return scriptingHandler
*/
public ScriptingHandler getScriptingHandler()
{
return scriptingHandler;
}
/**
* Set a handler to support JavaScript actions in the form.
*
* @param scriptingHandler
*/
public void setScriptingHandler(ScriptingHandler scriptingHandler)
{
this.scriptingHandler = scriptingHandler;
}
/**
* Set the AppendOnly bit.
*
* @param appendOnly The value for AppendOnly.
*/
public void setAppendOnly(boolean appendOnly)
{
dictionary.setFlag(COSName.SIG_FLAGS, FLAG_APPEND_ONLY, appendOnly);
}
private Matrix resolveTransformationMatrix(PDAnnotation annotation, PDAppearanceStream appearanceStream)
{
// 1st step transform appearance stream bbox with appearance stream matrix
Rectangle2D transformedAppearanceBox = getTransformedAppearanceBBox(appearanceStream);
PDRectangle annotationRect = annotation.getRectangle();
// 2nd step caclulate matrix to transform calculated rectangle into the annotation Rect boundaries
Matrix transformationMatrix = new Matrix();
transformationMatrix.translate((float) (annotationRect.getLowerLeftX()-transformedAppearanceBox.getX()), (float) (annotationRect.getLowerLeftY()-transformedAppearanceBox.getY()));
transformationMatrix.scale((float) (annotationRect.getWidth()/transformedAppearanceBox.getWidth()), (float) (annotationRect.getHeight()/transformedAppearanceBox.getHeight()));
return transformationMatrix;
}
/**
* Calculate the transformed appearance box.
*
* Apply the Matrix (or an identity transform) to the BBox of
* the appearance stream
*
* @param appearanceStream
* @return the transformed rectangle
*/
private Rectangle2D getTransformedAppearanceBBox(PDAppearanceStream appearanceStream)
{
Matrix appearanceStreamMatrix = appearanceStream.getMatrix();
PDRectangle appearanceStreamBBox = appearanceStream.getBBox();
GeneralPath transformedAppearanceBox = appearanceStreamBBox.transform(appearanceStreamMatrix);
return transformedAppearanceBox.getBounds2D();
}
private Map<COSDictionary,Set<COSDictionary>> buildPagesWidgetsMap(List<PDField> fields) throws IOException
{
Map<COSDictionary,Set<COSDictionary>> pagesAnnotationsMap = new HashMap<>();
boolean hasMissingPageRef = false;
for (PDField field : fields)
{
List<PDAnnotationWidget> widgets = field.getWidgets();
for (PDAnnotationWidget widget : widgets)
{
PDPage page = widget.getPage();
if (page != null)
{
fillPagesAnnotationMap(pagesAnnotationsMap, page, widget);
}
else
{
hasMissingPageRef = true;
}
}
}
if (!hasMissingPageRef)
{
return pagesAnnotationsMap;
}
// If there is a widget with a missing page reference we need to build the map reverse i.e.
// from the annotations to the widget.
LOG.warn("There has been a widget with a missing page reference, will check all page annotations");
for (PDPage page : document.getPages())
{
for (PDAnnotation annotation : page.getAnnotations())
{
if (annotation instanceof PDAnnotationWidget)
{
fillPagesAnnotationMap(pagesAnnotationsMap, page, (PDAnnotationWidget) annotation);
}
}
}
return pagesAnnotationsMap;
}
private void fillPagesAnnotationMap(Map<COSDictionary, Set<COSDictionary>> pagesAnnotationsMap,
PDPage page, PDAnnotationWidget widget)
{
if (pagesAnnotationsMap.get(page.getCOSObject()) == null)
{
Set<COSDictionary> widgetsForPage = new HashSet<>();
widgetsForPage.add(widget.getCOSObject());
pagesAnnotationsMap.put(page.getCOSObject(), widgetsForPage);
}
else
{
Set<COSDictionary> widgetsForPage = pagesAnnotationsMap.get(page.getCOSObject());
widgetsForPage.add(widget.getCOSObject());
}
}
private void removeFields(List<PDField> fields)
{
for (PDField field : fields)
{
COSArray array;
if (field.getParent() == null)
{
// if the field has no parent, assume it is at root level list, remove it from there
array = dictionary.getCOSArray(COSName.FIELDS);
}
else
{
// if the field has a parent, then remove from the list there
array = field.getParent().getCOSObject().getCOSArray(COSName.KIDS);
}
array.removeObject(field.getCOSObject());
}
}
}