com.openhtmltopdf.pdfboxout.PdfBoxAccessibilityHelper Maven / Gradle / Ivy
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Openhtmltopdf is a CSS 2.1 renderer written in Java. This artifact supports PDF output with Apache PDF-BOX 2.
package com.openhtmltopdf.pdfboxout;
import java.awt.geom.AffineTransform;
import java.awt.geom.Rectangle2D;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.function.Supplier;
import java.util.logging.Level;
import com.openhtmltopdf.util.LogMessageId;
import org.apache.pdfbox.cos.COSArray;
import org.apache.pdfbox.cos.COSDictionary;
import org.apache.pdfbox.cos.COSInteger;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.common.PDNumberTreeNode;
import org.apache.pdfbox.pdmodel.common.PDRectangle;
import org.apache.pdfbox.pdmodel.documentinterchange.logicalstructure.PDMarkedContentReference;
import org.apache.pdfbox.pdmodel.documentinterchange.logicalstructure.PDObjectReference;
import org.apache.pdfbox.pdmodel.documentinterchange.logicalstructure.PDStructureElement;
import org.apache.pdfbox.pdmodel.documentinterchange.logicalstructure.PDStructureTreeRoot;
import org.apache.pdfbox.pdmodel.documentinterchange.markedcontent.PDMarkedContent;
import org.apache.pdfbox.pdmodel.documentinterchange.taggedpdf.StandardStructureTypes;
import org.apache.pdfbox.pdmodel.interactive.annotation.PDAnnotation;
import org.apache.pdfbox.pdmodel.interactive.annotation.PDAnnotationLink;
import org.w3c.dom.Document;
import com.openhtmltopdf.css.constants.CSSName;
import com.openhtmltopdf.css.constants.IdentValue;
import com.openhtmltopdf.extend.StructureType;
import com.openhtmltopdf.newtable.TableCellBox;
import com.openhtmltopdf.render.BlockBox;
import com.openhtmltopdf.render.Box;
import com.openhtmltopdf.render.InlineLayoutBox;
import com.openhtmltopdf.render.LineBox;
import com.openhtmltopdf.render.MarkerData;
import com.openhtmltopdf.render.RenderingContext;
import com.openhtmltopdf.util.XRLog;
public class PdfBoxAccessibilityHelper {
// This maps from page to a list of content items, we need to process in page order, so a linked map.
private final Map _pageItemsMap = new LinkedHashMap<>();
private final PdfBoxFastOutputDevice _od;
private final Box _rootBox;
private final Document _doc;
private final GenericStructualElement _root;
private static final Map> _tagSuppliers = createTagSuppliers();
private int _nextMcid;
// These change with every page, most of them are only needed while we paint the page, so we don't add
// them to the PageItems class, which is stored for later processing.
private PageItems _pageItems;
private PdfContentStreamAdapter _cs;
private RenderingContext _ctx;
private PDPage _page;
private float _pageHeight;
private AffineTransform _transform;
private int _runningLevel;
private static Map> createTagSuppliers() {
Map> suppliers = new HashMap<>();
suppliers.put("ul", ListStructualElement::new);
suppliers.put("ol", ListStructualElement::new);
suppliers.put("li", ListItemStructualElement::new);
suppliers.put("table", TableStructualElement::new);
suppliers.put("tr", TableRowStructualElement::new);
suppliers.put("td", TableCellStructualElement::new);
suppliers.put("th", TableHeaderStructualElement::new);
suppliers.put("a", AnchorStuctualElement::new);
suppliers.put("abbr", AbbrStuctualElement::new);
return suppliers;
}
public PdfBoxAccessibilityHelper(PdfBoxFastOutputDevice od, Box root, Document doc) {
this._od = od;
this._rootBox = root;
this._doc = doc;
this._root = new GenericStructualElement();
this._root.box = root;
root.setAccessiblityObject(this._root);
}
private static class PageItems {
final List _contentItems = new ArrayList<>();
final List _pageAnnotations = new ArrayList<>();
}
/**
* Can be either a structure element or a content item.
*/
private static abstract class AbstractTreeItem {
AbstractStructualElement parent;
abstract void finish(AbstractStructualElement parent);
}
private static abstract class AbstractStructualElement extends AbstractTreeItem {
Box box;
PDStructureElement elem;
PDStructureElement parentElem; // May be different from this.parent.elem if we skip boxes in the tree.
PDPage page;
abstract void addChild(AbstractTreeItem child);
abstract String getPdfTag();
void createPdfStrucureElement(AbstractStructualElement parent, AbstractStructualElement child) {
child.parentElem = parent.elem;
child.elem = new PDStructureElement(child.getPdfTag(), child.parentElem);
child.elem.setParent(child.parentElem);
child.elem.setPage(child.page);
child.parentElem.appendKid(child.elem);
}
/**
* Handles globally valid HTML attributes such as title and lang.
*/
void handleGlobalAttributes() {
handleLangAttribute();
handleTitleAttribute();
}
void handleLangAttribute() {
if (box != null && box.getElement() != null) {
String lang = box.getElement().getAttribute("lang");
if (!lang.isEmpty()) {
this.elem.setLanguage(lang);
}
}
}
void handleTitleAttribute() {
if (box != null && box.getElement() != null) {
String alternate = box.getElement().getAttribute("title");
if (!alternate.isEmpty()) {
this.elem.setAlternateDescription(alternate);
}
}
}
/**
* Only a couple of types of structural elements need the PDF version
* so leave empty in the base class.
*/
void setPdfVersion(float version) { }
/**
* The optional attribute dictionary is used for additional information about
* the structural element such as bounding box, cell spans, etc.
* NOTE: This only allows one attribute dictionary (possibly with multiple attributes) with one owner.
*/
void setAttributeDictionary(COSDictionary attrDict) {
// NOTE: We could do this instead:
// this.elem.addAttribute(PDAttributeObject.create(attrDict));
// However, PDFBOX adds a revision number.
// This is allowed by the spec but causes the PDF Accessiblity Checker (PAC)
// to crash.
this.elem.getCOSObject().setItem(COSName.A, attrDict);
}
@Override
public String toString() {
return String.format("[Structual Element-%s:%s]", super.toString(), box);
}
}
private static class GenericStructualElement extends AbstractStructualElement {
final List children = new ArrayList<>();
@Override
String getPdfTag() {
return chooseTag(this.box);
}
@Override
void addChild(AbstractTreeItem child) {
this.children.add(child);
}
private String chooseTag(Box box) {
if (box != null) {
if (box.getLayer() != null) {
return StandardStructureTypes.SECT;
} else if (box.isAnonymous()) {
return guessBoxTag(box);
} if (box.getElement() != null) {
String htmlTag = box.getElement().getTagName();
if (htmlTag.equals("p")) {
return StandardStructureTypes.P;
} else if (htmlTag.equals("h1")) {
return StandardStructureTypes.H1;
} else if (htmlTag.equals("h2")) {
return StandardStructureTypes.H2;
} else if (htmlTag.equals("h3")) {
return StandardStructureTypes.H3;
} else if (htmlTag.equals("h4")) {
return StandardStructureTypes.H4;
} else if (htmlTag.equals("h5")) {
return StandardStructureTypes.H5;
} else if (htmlTag.equals("h6")) {
return StandardStructureTypes.H6;
} else if (htmlTag.equals("article")) {
return StandardStructureTypes.ART;
}
}
return guessBoxTag(box);
}
return StandardStructureTypes.SPAN;
}
@Override
void finish(AbstractStructualElement parent) {
// A structual element such as Div, Sect, p, etc
// which contains other structual elements or content items (text).
GenericStructualElement child = this;
if (child.children.isEmpty() &&
(child.box.getElement() == null || !child.box.getElement().hasAttribute("id"))) {
// There is no point in outputting empty structual elements.
// Exception is elements with an id which may be there to
// use as a link or bookmark destination.
return;
}
if (child.box instanceof LineBox ||
(child.box instanceof InlineLayoutBox &&
child.children.size() == 1 &&
child.box.getParent() instanceof LineBox)) {
// We skip (don't create structure element) line boxes in the tree.
// We also skip the common case of a intermediary InlineLayoutBox between the
// LineBox and a single InlineText.
finishTreeItems(child.children, parent);
} else {
createPdfStrucureElement(parent, child);
handleGlobalAttributes();
// Recursively, depth first, process the structual tree.
finishTreeItems(child.children, child);
}
}
}
private static class AnchorStuctualElement extends GenericStructualElement {
@Override
String getPdfTag() {
return StandardStructureTypes.LINK;
}
@Override
void finish(AbstractStructualElement parent) {
AnchorStuctualElement child = this;
createPdfStrucureElement(parent, child);
String alternate = box.getElement() != null ? box.getElement().getAttribute("title") : "";
if (alternate.isEmpty()) {
XRLog.log(Level.INFO, LogMessageId.LogMessageId1Param.GENERAL_PDF_ACCESSIBILITY_NO_TITLE_TEXT_PROVIDED_FOR, "link");
}
child.elem.setAlternateDescription(alternate);
handleLangAttribute();
finishTreeItems(child.children, child);
}
}
private static class AbbrStuctualElement extends GenericStructualElement {
float pdfVersion = 1.5f;
@Override
String getPdfTag() {
return StandardStructureTypes.SPAN;
}
@Override
void finish(AbstractStructualElement parent) {
AbbrStuctualElement child = this;
createPdfStrucureElement(parent, child);
if (box.getElement() != null) {
String expanded = box.getElement().getAttribute("title");
if (!expanded.isEmpty()) {
if (pdfVersion < 1.5f) {
// The expanded entry for structural elements was only introduced in 1.5.
child.elem.setAlternateDescription(expanded);
} else {
child.elem.setExpandedForm(expanded);
}
} else {
XRLog.log(Level.INFO, LogMessageId.LogMessageId1Param.GENERAL_PDF_ACCESSIBILITY_NO_TITLE_TEXT_PROVIDED_FOR, "abbr tag");
}
handleLangAttribute();
}
finishTreeItems(child.children, child);
}
@Override
void setPdfVersion(float version) {
this.pdfVersion = version;
}
}
private static class ListStructualElement extends AbstractStructualElement {
final List listItems = new ArrayList<>();
@Override
String getPdfTag() {
return StandardStructureTypes.L;
}
@Override
void addChild(AbstractTreeItem child) {
if (child instanceof ListItemStructualElement) {
this.listItems.add((ListItemStructualElement) child);
} else {
logIncompatibleChild(this, child, ListItemStructualElement.class);
}
}
@Override
void finish(AbstractStructualElement parent) {
ListStructualElement child = this;
createPdfStrucureElement(parent, child);
IdentValue listStyleType = child.box.getStyle().getIdent(CSSName.LIST_STYLE_TYPE);
String listType;
if (listStyleType == IdentValue.NONE) {
listType = "None";
} else if (listStyleType == IdentValue.DISC) {
listType = "Disc";
} else if (listStyleType == IdentValue.SQUARE) {
listType = "Square";
} else if (listStyleType == IdentValue.CIRCLE) {
listType = "Circle";
} else if (listStyleType == IdentValue.DECIMAL ||
listStyleType == IdentValue.DECIMAL_LEADING_ZERO) {
listType = "Decimal";
} else if (listStyleType == IdentValue.UPPER_ROMAN) {
listType = "UpperRoman";
} else if (listStyleType == IdentValue.LOWER_ROMAN) {
listType = "LowerRoman";
} else if (listStyleType == IdentValue.UPPER_ALPHA) {
listType = "UpperAlpha";
} else if (listStyleType == IdentValue.LOWER_ALPHA) {
listType = "LowerAlpha";
} else {
// Armenian, Georgian, Latin and Greek are not supported by the PDF spec.
listType = "Decimal";
}
COSDictionary listNumbering = new COSDictionary();
listNumbering.setItem(COSName.O, COSName.getPDFName("List"));
listNumbering.setItem(COSName.getPDFName("ListNumbering"), COSName.getPDFName(listType));
setAttributeDictionary(listNumbering);
handleGlobalAttributes();
finishTreeItems(child.listItems, child);
}
}
private static class ListItemStructualElement extends AbstractStructualElement {
final ListLabelStructualElement label;
final ListBodyStructualElement body;
ListItemStructualElement() {
this.body = new ListBodyStructualElement();
this.body.parent = this;
this.label = new ListLabelStructualElement();
this.label.parent = this;
}
@Override
String getPdfTag() {
return StandardStructureTypes.LI;
}
@Override
void addChild(AbstractTreeItem child) {
this.body.addChild(child);
}
@Override
void finish(AbstractStructualElement parent) {
ListItemStructualElement child = this;
createPdfStrucureElement(parent, child);
handleGlobalAttributes();
finishTreeItem(child.label, child);
finishTreeItem(child.body, child);
}
}
private static class ListLabelStructualElement extends AbstractStructualElement {
final List children = new ArrayList<>(1);
@Override
String getPdfTag() {
return StandardStructureTypes.LBL;
}
@Override
void addChild(AbstractTreeItem child) {
this.children.add(child);
}
@Override
void finish(AbstractStructualElement parent) {
ListLabelStructualElement child = this;
if (child.children.isEmpty()) {
// Must be list-style-type: none.
return;
}
createPdfStrucureElement(parent, child);
handleGlobalAttributes();
finishTreeItems(child.children, child);
}
}
private static class ListBodyStructualElement extends GenericStructualElement {
@Override
String getPdfTag() {
return StandardStructureTypes.L_BODY;
}
@Override
void finish(AbstractStructualElement parent) {
ListBodyStructualElement child = this;
createPdfStrucureElement(parent, child);
handleGlobalAttributes();
finishTreeItems(child.children, child);
}
}
private static class TableStructualElement extends AbstractStructualElement {
final TableHeadStructualElement thead = new TableHeadStructualElement();
final List tbodies = new ArrayList<>(1);
final TableFootStructualElement tfoot = new TableFootStructualElement();
float pdfVersion = 1.5f;
@Override
void addChild(AbstractTreeItem child) {
if (child instanceof TableBodyStructualElement) {
this.tbodies.add((TableBodyStructualElement) child);
} else {
logIncompatibleChild(parent, child, TableBodyStructualElement.class);
}
}
@Override
void setPdfVersion(float version) {
this.pdfVersion = version;
}
@Override
String getPdfTag() {
return StandardStructureTypes.TABLE;
}
@Override
void finish(AbstractStructualElement parent) {
TableStructualElement child = this;
createPdfStrucureElement(parent, child);
handleGlobalAttributes();
if (pdfVersion < 1.5f) {
// THead, TBody and TFoot were introduced in PDF 1.5 so if we can not use
// them then we process their rows directly and add them to the table.
finishTreeItems(child.thead.children, child);
child.tbodies.forEach(tbody -> finishTreeItems(tbody.children, child));
finishTreeItems(child.tfoot.children, child);
} else {
finishTreeItem(child.thead, child);
finishTreeItems(child.tbodies, child);
finishTreeItem(child.tfoot, child);
}
}
}
private static class TableHeadStructualElement extends GenericStructualElement {
@Override
String getPdfTag() {
return StandardStructureTypes.T_HEAD;
}
@Override
void addChild(AbstractTreeItem child) {
if (!(child instanceof TableRowStructualElement)) {
logIncompatibleChild(this, child, TableRowStructualElement.class);
}
super.addChild(child);
}
@Override
void finish(AbstractStructualElement parent) {
TableHeadStructualElement child = this;
createPdfStrucureElement(parent, child);
handleGlobalAttributes();
finishTreeItems(child.children, child);
}
}
private static class TableBodyStructualElement extends GenericStructualElement {
@Override
String getPdfTag() {
return StandardStructureTypes.T_BODY;
}
@Override
void addChild(AbstractTreeItem child) {
if (!(child instanceof TableRowStructualElement)) {
logIncompatibleChild(this, child, TableRowStructualElement.class);
}
super.addChild(child);
}
@Override
void finish(AbstractStructualElement parent) {
TableBodyStructualElement child = this;
createPdfStrucureElement(parent, child);
handleGlobalAttributes();
finishTreeItems(child.children, child);
}
}
private static class TableFootStructualElement extends GenericStructualElement {
@Override
String getPdfTag() {
return StandardStructureTypes.T_FOOT;
}
@Override
void addChild(AbstractTreeItem child) {
if (!(child instanceof TableRowStructualElement)) {
logIncompatibleChild(this, child, TableRowStructualElement.class);
}
super.addChild(child);
}
@Override
void finish(AbstractStructualElement parent) {
TableFootStructualElement child = this;
createPdfStrucureElement(parent, child);
handleGlobalAttributes();
finishTreeItems(child.children, child);
}
}
private static class TableRowStructualElement extends GenericStructualElement {
@Override
String getPdfTag() {
return StandardStructureTypes.TR;
}
@Override
void addChild(AbstractTreeItem child) {
if (!(child instanceof TableHeaderOrCellStructualElement)) {
logIncompatibleChild(this, child, TableHeaderOrCellStructualElement.class);
}
super.addChild(child);
}
@Override
void finish(AbstractStructualElement parent) {
TableRowStructualElement child = this;
createPdfStrucureElement(parent, child);
handleGlobalAttributes();
finishTreeItems(child.children, child);
}
}
private static abstract class TableHeaderOrCellStructualElement extends GenericStructualElement {
boolean addCellAttributes(COSDictionary attrDict) {
TableHeaderOrCellStructualElement child = this;
boolean added = false;
int rowSpanAttr = 1;
int colSpanAttr = 1;
if (child.box instanceof TableCellBox) {
TableCellBox cell = (TableCellBox) box;
colSpanAttr = cell.getStyle().getColSpan();
rowSpanAttr = cell.getStyle().getRowSpan();
}
if (colSpanAttr != 1) {
added = true;
attrDict.setInt(COSName.getPDFName("ColSpan"), colSpanAttr);
}
if (rowSpanAttr != 1) {
added = true;
attrDict.setInt(COSName.getPDFName("RowSpan"), rowSpanAttr);
}
return added;
}
}
private static class TableHeaderStructualElement extends TableHeaderOrCellStructualElement {
@Override
String getPdfTag() {
return StandardStructureTypes.TH;
}
@Override
void finish(AbstractStructualElement parent) {
TableHeaderStructualElement child = this;
createPdfStrucureElement(parent, child);
String scope = box.getElement() != null ? box.getElement().getAttribute("scope") : "";
COSDictionary attrDict = new COSDictionary();
attrDict.setItem(COSName.O, COSName.getPDFName("Table"));
if ("row".equals(scope)) {
attrDict.setItem(COSName.getPDFName("Scope"), COSName.getPDFName("Row"));
} else {
attrDict.setItem(COSName.getPDFName("Scope"), COSName.getPDFName("Column"));
}
addCellAttributes(attrDict);
setAttributeDictionary(attrDict);
handleGlobalAttributes();
finishTreeItems(child.children, child);
}
}
private static class TableCellStructualElement extends TableHeaderOrCellStructualElement {
@Override
String getPdfTag() {
return StandardStructureTypes.TD;
}
@Override
void finish(AbstractStructualElement parent) {
TableCellStructualElement child = this;
createPdfStrucureElement(parent, child);
COSDictionary attrDict = new COSDictionary();
attrDict.setItem(COSName.O, COSName.getPDFName("Table"));
if (addCellAttributes(attrDict)) {
setAttributeDictionary(attrDict);
}
handleGlobalAttributes();
finishTreeItems(child.children, child);
}
}
private static class FigureStructualElement extends AbstractStructualElement {
PDRectangle boundingBox;
FigureContentItem content;
@Override
String getPdfTag() {
return StandardStructureTypes.Figure;
}
@Override
void addChild(AbstractTreeItem child) {
if (child instanceof FigureContentItem) {
this.content = (FigureContentItem) child;
} else {
logIncompatibleChild(parent, child, FigureContentItem.class);
}
}
@Override
void finish(AbstractStructualElement parent) {
// Must be a figure (image or replaced, etc).
FigureStructualElement child = this;
child.parentElem = parent.elem;
child.elem = new PDStructureElement(child.getPdfTag(), child.parentElem);
child.elem.setParent(child.parentElem);
child.elem.setPage(child.page);
// Add alt text.
String alternateText = child.box.getElement() == null ? "" : box.getElement().getAttribute("alt");
if (alternateText.isEmpty()) {
XRLog.log(Level.WARNING, LogMessageId.LogMessageId0Param.GENERAL_PDF_ACCESSIBILITY_NO_ALT_ATTRIBUTE_PROVIDED_FOR_IMAGE);
}
child.elem.setAlternateDescription(alternateText);
handleLangAttribute();
// Add bounding box attribute.
COSDictionary attributeDict = new COSDictionary();
attributeDict.setItem(COSName.BBOX, child.boundingBox);
attributeDict.setItem(COSName.O, COSName.getPDFName("Layout"));
setAttributeDictionary(attributeDict);
child.parentElem.appendKid(child.elem);
finishTreeItem(child.content, child);
}
}
private static class GenericContentItem extends AbstractTreeItem {
PDStructureElement parentElem;
int mcid;
COSDictionary dict;
PDPage page;
@Override
public String toString() {
return String.format("[Content Item-%s:%d]", super.toString(), mcid);
}
@Override
void finish(AbstractStructualElement parent) {
// A content item (text or replaced image), we need to add it to its parent structual item.
GenericContentItem child = this;
boolean isReplaced = child instanceof FigureContentItem;
if (child.page == parent.page) {
// If this is on the same page as its parent structual element
// we can just use the dict with mcid in it only.
child.parentElem = parent.elem;
child.parentElem.appendKid(new PDMarkedContent(isReplaced ? COSName.getPDFName("Figure") : COSName.getPDFName("Span"), child.dict));
} else {
// Otherwise we need a more complete dict with the page.
child.parentElem = parent.elem;
child.dict = new COSDictionary();
child.dict.setItem(COSName.TYPE, COSName.getPDFName("MCR"));
child.dict.setItem(COSName.PG, child.page);
child.dict.setInt(COSName.MCID, child.mcid);
PDMarkedContentReference ref = new PDMarkedContentReference(child.dict);
child.parentElem.appendKid(ref);
}
}
}
private static class FigureContentItem extends GenericContentItem {
}
private static void logIncompatibleChild(AbstractTreeItem parent, AbstractTreeItem child, Class expected) {
XRLog.log(Level.WARNING, LogMessageId.LogMessageId3Param.GENERAL_PDF_ACCESSIBILITY_INCOMPATIBLE_CHILD, child.getClass().getSimpleName(), parent.getClass().getSimpleName(), expected.getSimpleName());
}
/**
* Given a box, gets its structual element.
*/
public static PDStructureElement getStructualElementForBox(Box targetBox) {
if (targetBox != null &&
targetBox.getAccessibilityObject() != null &&
targetBox.getAccessibilityObject() instanceof AbstractStructualElement) {
return ((AbstractStructualElement) targetBox.getAccessibilityObject()).elem;
}
return null;
}
public void finishPdfUa() {
PDStructureTreeRoot root = _od.getWriter().getDocumentCatalog().getStructureTreeRoot();
if (root == null) {
root = new PDStructureTreeRoot();
HashMap roleMap = new HashMap<>();
roleMap.put("Annotation", "Span");
roleMap.put("Artifact", "P");
roleMap.put("Bibliography", "BibEntry");
roleMap.put("Chart", "Figure");
roleMap.put("Diagram", "Figure");
roleMap.put("DropCap", "Figure");
roleMap.put("EndNote", "Note");
roleMap.put("FootNote", "Note");
roleMap.put("InlineShape", "Figure");
roleMap.put("Outline", "Span");
roleMap.put("Strikeout", "Span");
roleMap.put("Subscript", "Span");
roleMap.put("Superscript", "Span");
roleMap.put("Underline", "Span");
root.setRoleMap(roleMap);
PDStructureElement rootElem = new PDStructureElement(StandardStructureTypes.DOCUMENT, null);
String lang = _doc.getDocumentElement().getAttribute("lang");
rootElem.setLanguage(lang.isEmpty() ? "EN-US" : lang);
root.appendKid(rootElem);
_root.elem = rootElem;
finishTreeItems(_root.children, _root);
_od.getWriter().getDocumentCatalog().setStructureTreeRoot(root);
}
}
public void finishNumberTree() {
COSArray numTree = new COSArray();
int i = 0;
for (Map.Entry entry : _pageItemsMap.entrySet()) {
List pageItems = entry.getValue()._contentItems;
List pageAnnotations = entry.getValue()._pageAnnotations;
COSArray mcidParentReferences = new COSArray();
for (GenericContentItem contentItem : pageItems) {
mcidParentReferences.add(contentItem.parentElem);
}
numTree.add(COSInteger.get(i));
numTree.add(mcidParentReferences);
entry.getKey().getCOSObject().setItem(COSName.STRUCT_PARENTS, COSInteger.get(i));
entry.getKey().getCOSObject().setItem(COSName.getPDFName("Tabs"), COSName.S);
i++;
for (AnnotationWithStructureParent annot : pageAnnotations) {
numTree.add(COSInteger.get(i));
numTree.add(annot.structureParent);
annot.annotation.setStructParent(i);
i++;
}
}
COSDictionary dict = new COSDictionary();
dict.setItem(COSName.NUMS, numTree);
PDNumberTreeNode numberTreeNode = new PDNumberTreeNode(dict, dict.getClass());
_od.getWriter().getDocumentCatalog().getStructureTreeRoot().setParentTreeNextKey(i);
_od.getWriter().getDocumentCatalog().getStructureTreeRoot().setParentTree(numberTreeNode);
}
private static String guessBoxTag(Box box) {
if (box instanceof BlockBox) {
BlockBox block = (BlockBox) box;
if (block.isInline()) {
return StandardStructureTypes.SPAN;
} else {
return StandardStructureTypes.DIV;
}
} else {
return StandardStructureTypes.SPAN;
}
}
private static void finishTreeItems(List children, AbstractStructualElement parent) {
for (AbstractTreeItem child : children) {
child.finish(parent);
}
}
private static void finishTreeItem(AbstractTreeItem item, AbstractStructualElement parent) {
item.finish(parent);
}
private COSDictionary createMarkedContentDictionary() {
COSDictionary dict = new COSDictionary();
dict.setInt(COSName.MCID, _nextMcid);
_nextMcid++;
return dict;
}
private void ensureAncestorTree(AbstractTreeItem child, Box parent) {
// Walk up the ancestor tree making sure they all have accessibility objects.
while (parent != null && parent.getAccessibilityObject() == null) {
AbstractStructualElement parentItem = createStructureItem(null, parent);
parent.setAccessiblityObject(parentItem);
parentItem.addChild(child);
child.parent = parentItem;
child = parentItem;
parent = parent.getParent();
}
}
private AbstractStructualElement createStructureItem(StructureType type, Box box) {
AbstractStructualElement child = null;
if (box instanceof BlockBox) {
BlockBox bb = (BlockBox) box;
if (bb.isReplaced()) {
// For replaced elements we will need to create a BBox.
// This is done here so we don'thave to hang onto the page height, transform, etc.
Rectangle2D rect = PdfBoxFastLinkManager.createTargetArea(
_ctx, box, _pageHeight, _transform, _rootBox, _od);
child = new FigureStructualElement();
((FigureStructualElement) child).boundingBox = new PDRectangle(
(float) rect.getMinX(),
(float) rect.getMinY(),
(float) rect.getWidth(),
(float) rect.getHeight());
}
}
if (child == null && box.getElement() != null && !box.isAnonymous()) {
String htmlTag = box.getElement().getTagName();
Supplier supplier = _tagSuppliers.get(htmlTag);
if (supplier != null) {
child = supplier.get();
}
}
if (child == null &&
box.getParent() != null &&
box.getParent().getAccessibilityObject() instanceof TableStructualElement) {
TableStructualElement table = (TableStructualElement) box.getParent().getAccessibilityObject();
table.setPdfVersion(_od.getWriter().getVersion());
if (box.getStyle().isIdent(CSSName.DISPLAY, IdentValue.TABLE_HEADER_GROUP)) {
child = table.thead;
} else if (box.getStyle().isIdent(CSSName.DISPLAY, IdentValue.TABLE_ROW_GROUP)) {
child = new TableBodyStructualElement();
} else if (box.getStyle().isIdent(CSSName.DISPLAY, IdentValue.TABLE_FOOTER_GROUP)) {
child = table.tfoot;
}
}
if (child == null) {
child = new GenericStructualElement();
}
child.page = _page;
child.box = box;
child.setPdfVersion(_od.getWriter().getVersion());
return child;
}
private void setupStructureElement(AbstractStructualElement child, Box box) {
box.setAccessiblityObject(child);
ensureAncestorTree(child, box.getParent());
ensureParent(box, child);
}
private void ensureParent(Box box, AbstractTreeItem child) {
if (child.parent == null) {
if (child instanceof TableHeadStructualElement ||
child instanceof TableFootStructualElement) {
child.parent = (TableStructualElement) box.getParent().getAccessibilityObject();
} else if (child instanceof TableBodyStructualElement) {
child.parent = (TableStructualElement) box.getParent().getAccessibilityObject();
((TableStructualElement) child.parent).tbodies.add((TableBodyStructualElement) child);
} else if (box.getParent() != null) {
AbstractStructualElement parent = (AbstractStructualElement) box.getParent().getAccessibilityObject();
parent.addChild(child);
child.parent = parent;
} else {
_root.children.add(child);
child.parent = _root;
}
}
}
private GenericContentItem createMarkedContentStructureItem(StructureType type, Box box) {
GenericContentItem current = new GenericContentItem();
ensureAncestorTree(current, box.getParent());
AbstractStructualElement parent = (AbstractStructualElement) box.getAccessibilityObject();
parent.addChild(current);
current.parent = parent;
current.mcid = _nextMcid;
current.dict = createMarkedContentDictionary();
current.page = _page;
_pageItems._contentItems.add(current);
return current;
}
private GenericContentItem createListItemLabelMarkedContent(StructureType type, Box box) {
GenericContentItem current = new GenericContentItem();
current.mcid = _nextMcid;
current.dict = createMarkedContentDictionary();
current.page = _page;
ListItemStructualElement li = (ListItemStructualElement) box.getAccessibilityObject();
li.label.addChild(current);
current.parent = li.label;
_pageItems._contentItems.add(current);
return current;
}
private FigureContentItem createFigureContentStructureItem(StructureType type, Box box) {
FigureStructualElement parent = (FigureStructualElement) box.getAccessibilityObject();
if (parent == null ||
parent.content != null) {
// This figure structual element already has an image associatted with it.
// Images continued on subsequent pages will be treated as artifacts.
return null;
}
FigureContentItem current = new FigureContentItem();
ensureAncestorTree(current, box.getParent());
current.parent = parent;
current.mcid = _nextMcid;
current.dict = createMarkedContentDictionary();
current.page = _page;
parent.content = current;
_pageItems._contentItems.add(current);
return current;
}
private COSDictionary createBackgroundArtifact(StructureType type, Box box) {
Rectangle2D rect = PdfBoxFastLinkManager.createTargetArea(_ctx, box, _pageHeight, _transform, _rootBox, _od);
PDRectangle pdRect = new PDRectangle((float) rect.getMinX(), (float) rect.getMinY(), (float) rect.getWidth(), (float) rect.getHeight());
COSDictionary dict = new COSDictionary();
dict.setItem(COSName.TYPE, COSName.BACKGROUND);
dict.setItem(COSName.BBOX, pdRect);
return dict;
}
private COSDictionary createPaginationArtifact(StructureType type, Box box) {
COSDictionary dict = new COSDictionary();
dict.setItem(COSName.TYPE, COSName.getPDFName("Pagination"));
return dict;
}
private static class Token {
}
private static final Token TRUE_TOKEN = new Token();
private static final Token FALSE_TOKEN = new Token();
private static final Token INSIDE_RUNNING = new Token();
private static final Token STARTING_RUNNING = new Token();
private static final Token NESTED_RUNNING = new Token();
public Token startStructure(StructureType type, Box box) {
// Check for items that appear on every page (fixed, running, page margins).
if (type == StructureType.RUNNING) {
// Only mark artifact for first level of running element (we might have
// nested fixed elements).
if (_runningLevel == 0) {
_runningLevel++;
COSDictionary run = createPaginationArtifact(type, box);
_cs.beginMarkedContent(COSName.ARTIFACT, run);
return STARTING_RUNNING;
}
_runningLevel++;
return NESTED_RUNNING;
} else if (_runningLevel > 0) {
// We are in a running artifact.
return INSIDE_RUNNING;
}
switch (type) {
case LAYER:
case FLOAT:
case BLOCK:
case INLINE:
case INLINE_CHILD_BOX: {
AbstractStructualElement struct = (AbstractStructualElement) box.getAccessibilityObject();
if (struct == null) {
struct = createStructureItem(type, box);
setupStructureElement(struct, box);
}
return FALSE_TOKEN;
}
case BACKGROUND: {
if (box.hasNonTextContent(_ctx)) {
COSDictionary current = createBackgroundArtifact(type, box);
_cs.beginMarkedContent(COSName.ARTIFACT, current);
return TRUE_TOKEN;
}
return FALSE_TOKEN;
}
case LIST_MARKER: {
if (box instanceof BlockBox) {
MarkerData markers = ((BlockBox) box).getMarkerData();
if (markers == null ||
(markers.getGlyphMarker() == null &&
markers.getTextMarker() == null &&
markers.getImageMarker() == null)) {
return FALSE_TOKEN;
}
}
GenericContentItem current = createListItemLabelMarkedContent(type, box);
_cs.beginMarkedContent(COSName.getPDFName("Span"), current.dict);
return TRUE_TOKEN;
}
case TEXT: {
GenericContentItem current = createMarkedContentStructureItem(type, box);
_cs.beginMarkedContent(COSName.getPDFName(StandardStructureTypes.SPAN), current.dict);
return TRUE_TOKEN;
}
case REPLACED: {
AbstractStructualElement struct = (AbstractStructualElement) box.getAccessibilityObject();
if (struct == null) {
struct = createStructureItem(type, box);
setupStructureElement(struct, box);
}
FigureContentItem current = createFigureContentStructureItem(type, box);
if (current != null) {
_cs.beginMarkedContent(COSName.getPDFName(StandardStructureTypes.Figure), current.dict);
return TRUE_TOKEN;
} else {
// For images that continue over more than one page, just mark the portion on the second
// and subsequent pages as an artifact. The spec (PDF 1.7) is not clear on what to do in this
// situation.
COSDictionary bg = createBackgroundArtifact(type, box);
_cs.beginMarkedContent(COSName.ARTIFACT, bg);
return TRUE_TOKEN;
}
}
default: {
return FALSE_TOKEN;
}
}
}
public void endStructure(Object token) {
Token value = (Token) token;
if (value == TRUE_TOKEN) {
_cs.endMarkedContent();
} else if (value == FALSE_TOKEN ||
value == INSIDE_RUNNING) {
// do nothing...
} else if (value == NESTED_RUNNING) {
_runningLevel--;
} else if (value == STARTING_RUNNING) {
_runningLevel--;
_cs.endMarkedContent();
}
}
public void startPage(PDPage page, PdfContentStreamAdapter cs, RenderingContext ctx, float pageHeight, AffineTransform transform) {
this._cs = cs;
this._ctx = ctx;
this._nextMcid = 0;
this._page = page;
this._pageHeight = pageHeight;
this._transform = transform;
this._pageItems = new PageItems();
this._pageItemsMap.put(page, this._pageItems);
}
public void endPage() {
}
private static class AnnotationWithStructureParent {
PDStructureElement structureParent;
PDAnnotation annotation;
}
public void addLink(Box anchor, Box target, PDAnnotationLink annotation, PDPage page) {
PDStructureElement struct = getStructualElementForBox(anchor);
if (struct != null) {
// We have to append the link annotationobject reference as a kid of its associated structure element.
PDObjectReference ref = new PDObjectReference();
ref.setReferencedObject(annotation);
struct.appendKid(ref);
// We also need to save the pair so we can add it to the number tree for reverse lookup.
AnnotationWithStructureParent annotStructParentPair = new AnnotationWithStructureParent();
annotStructParentPair.annotation = annotation;
annotStructParentPair.structureParent = struct;
_pageItems._pageAnnotations.add(annotStructParentPair);
}
}
}