test/java/org/apache/fop/render/pdf/StructureTreeMergerTestCase.java - xmlgraphics-fop-pdf-images - Git at Google

 /*
  * 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.fop.render.pdf;

 import java.awt.Rectangle;
 import java.awt.geom.Rectangle2D;
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;

 import org.junit.Assert;
 import org.junit.Before;
 import org.junit.Test;

 import static org.junit.Assert.assertEquals;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;

 import org.apache.pdfbox.cos.COSArray;
 import org.apache.pdfbox.cos.COSDictionary;
 import org.apache.pdfbox.cos.COSName;
 import org.apache.pdfbox.cos.COSObject;

 import org.apache.pdfbox.pdmodel.PDDocument;
 import org.apache.pdfbox.pdmodel.PDPage;

 import org.apache.fop.events.DefaultEventBroadcaster;

 import org.apache.fop.pdf.PDFArray;
 import org.apache.fop.pdf.PDFDictionary;
 import org.apache.fop.pdf.PDFDocument;
 import org.apache.fop.pdf.PDFName;
 import org.apache.fop.pdf.PDFNumber;
 import org.apache.fop.pdf.PDFObject;
 import org.apache.fop.pdf.PDFPage;
 import org.apache.fop.pdf.PDFReference;
 import org.apache.fop.pdf.PDFResources;
 import org.apache.fop.pdf.PDFStructElem;
 import org.apache.fop.pdf.StandardStructureTypes;
 import org.apache.fop.pdf.StructureType;

 import org.apache.fop.render.pdf.pdfbox.PDFBoxAdapter;
 import org.apache.fop.render.pdf.pdfbox.PDFBoxAdapterTestCase;
 import org.apache.fop.render.pdf.pdfbox.PageParentTreeFinder;
 import org.apache.fop.render.pdf.pdfbox.StructureTreeMerger;

 public class StructureTreeMergerTestCase {
     private static final String LINK = "linkTagged.pdf";
     private static final String BrokenLink = "brokenLink.pdf";
     private static final String MissingOBJR = "missingOBJR.pdf";
     private static final String CONTENT = "content";

     private PDFPage pdfPage;
     private PDFDocument pdfDoc;
     private PDFBoxAdapter adapter;

     @Test
     public void testCopyStructure() throws IOException {
         PDDocument doc = PDFBoxAdapterTestCase.load(LINK);
         PDPage srcPage = doc.getPage(0);
         PageParentTreeFinder finder = new PageParentTreeFinder(srcPage);
         COSArray markedContentParents = finder.getPageParentTreeArray(doc);
         PDFStructElem elem = new PDFStructElem();
         elem.setObjectNumber(2);
         adapter = new PDFBoxAdapter(pdfPage, new HashMap<>(), new HashMap<>(), new HashMap<>(), new HashMap<>(),
                 new DefaultEventBroadcaster());
         adapter.setCurrentMCID(1);
         PDFLogicalStructureHandler handler = setUpPDFLogicalStructureHandler();
         StructureTreeMerger merger = new StructureTreeMerger(elem, handler, adapter, srcPage);
         merger.copyStructure(markedContentParents);
         PDFArray array = handler.getPageParentTree();
         checkMarkedContentsParentsForLinkTest(array);
         PDFStructElem first = (PDFStructElem)array.get(0);
         checkParentForLinkTest(first, 0);
         doc.close();
     }

     @Test
     public void testNullEntriesInParentTree() throws IOException {
         PDDocument doc = PDFBoxAdapterTestCase.load(LINK);
         PDPage srcPage = doc.getPage(0);
         PageParentTreeFinder finder = new PageParentTreeFinder(srcPage);
         COSArray markedContentParents = finder.getPageParentTreeArray(doc);
         markedContentParents.add(0, null);
         PDFStructElem elem = new PDFStructElem();
         elem.setObjectNumber(2);
         adapter = new PDFBoxAdapter(pdfPage, new HashMap<>(), new HashMap<>(), new HashMap<>(), new HashMap<>(),
                 new DefaultEventBroadcaster());
         PDFLogicalStructureHandler handler = setUpPDFLogicalStructureHandler();
         StructureTreeMerger merger = new StructureTreeMerger(elem, handler, adapter, srcPage);
         merger.copyStructure(markedContentParents);
         PDFArray array = handler.getPageParentTree();
         Assert.assertNull(array.get(0));
         doc.close();
     }

     @Test
     public void testOBJRCorrectPosition() throws IOException {
         PDDocument doc = PDFBoxAdapterTestCase.load(MissingOBJR);
         PDPage srcPage = doc.getPage(0);
         PageParentTreeFinder finder = new PageParentTreeFinder(srcPage);
         COSArray markedContentParents = finder.getPageParentTreeArray(doc);
         PDFStructElem elem = new PDFStructElem();
         elem.setObjectNumber(2);
         adapter = new PDFBoxAdapter(pdfPage, new HashMap<>(), new HashMap<>(), new HashMap<>(), new HashMap<>(),
                 new DefaultEventBroadcaster());
         PDFLogicalStructureHandler handler = setUpPDFLogicalStructureHandler();
         StructureTreeMerger merger = new StructureTreeMerger(elem, handler, adapter, srcPage);
         merger.copyStructure(markedContentParents);
         doc.close();
 //        PDFArray array = handler.getPageParentTree();

 //        PDFStructElem kid = (PDFStructElem)array.get(0);
 //        PDFReference reference = (PDFReference) kid.get("P");
 //        PDFStructElem parent = (PDFStructElem)reference.getObject();
 //        List<PDFObject> kids = parent.getKids();
 //        PDFDictionary first = (PDFDictionary) kids.get(0);

 //        Assert.assertEquals(first.get("Type").toString(), "/OBJR");
 //        PDFDictionary last = (PDFDictionary) kids.get(2);
 //        Assert.assertEquals(last.get("Type").toString(), "/OBJR");

 //        PDFStructElem middle = (PDFStructElem) kids.get(1);
 //        Assert.assertEquals(middle.get("Type").toString(), "/StructElem");
     }

     private void checkMarkedContentsParentsForLinkTest(PDFArray array) {
         PDFStructElem first = (PDFStructElem)array.get(0);
         List<PDFObject> firstKids = first.getKids();
         PDFDictionary firstKid = (PDFDictionary) firstKids.get(0);
         int test = ((PDFNumber)firstKid.get("MCID")).getNumber().intValue();
         int expected = 1;
         assertEquals(test, expected);
         PDFDictionary firstKidSibling = (PDFDictionary) firstKids.get(2);
         test = ((PDFNumber)firstKidSibling.get("MCID")).getNumber().intValue();
         expected = 3;
         assertEquals(test, expected);
         PDFStructElem second = (PDFStructElem)array.get(1);
         List<PDFObject> secondKids = second.getKids();
         PDFDictionary secKid = (PDFDictionary) secondKids.get(0);
         test = ((PDFNumber)secKid.get("MCID")).getNumber().intValue();
         expected = 2;
         assertEquals(test, expected);
     }

     private void checkParentForLinkTest(PDFStructElem elem, int index) {
         String [] types = {"Sect"};
         PDFStructElem parent = (PDFStructElem)((PDFReference)elem.get("P")).getObject();
         if (index < types.length) {
             String test = ((PDFName)parent.get("S")).getName();
             String expected = types[index];
             assertEquals(test, expected);
             index++;
             checkParentForLinkTest(parent, index);
         }
     }

     @Before
     public void setUp() {
         Rectangle2D r = new Rectangle2D.Double();
         pdfDoc = new PDFDocument(" ");
         pdfPage = new PDFPage(new PDFResources(pdfDoc), 0, r, r, r, r);
         pdfDoc.makeStructTreeRoot(null);
         pdfPage.setObjectNumber(1);
         pdfPage.setDocument(pdfDoc);
     }

     private PDFLogicalStructureHandler setUpPDFLogicalStructureHandler() {
         PDFLogicalStructureHandler handler = new PDFLogicalStructureHandler(pdfDoc);
         handler.getParentTree().setDocument(pdfDoc);
         handler.startPage(pdfPage);
         return handler;
     }

     @Test
     public void testCheckNullCOSObject() throws IOException {
         PDDocument doc = PDFBoxAdapterTestCase.load(BrokenLink);
         PDPage srcPage = doc.getPage(0);
         PageParentTreeFinder finder = new PageParentTreeFinder(srcPage);
         COSArray markedContentParents = finder.getPageParentTreeArray(doc);
         COSObject nullObj = new COSObject(null);
 //        nullObj.setObjectNumber(100);
 //        nullObj.setGenerationNumber(0);
         PDFStructElem elem = new PDFStructElem();
         elem.setObjectNumber(2);
         COSObject parent = (COSObject)markedContentParents.get(1);
         COSDictionary dict = (COSDictionary) parent.getObject();
         COSArray kids = (COSArray) dict.getDictionaryObject(COSName.K);
         COSDictionary kid = (COSDictionary) kids.get(1);
         kid.setItem(COSName.OBJ, nullObj);
         adapter = new PDFBoxAdapter(pdfPage, new HashMap<>(), new HashMap<>(), new HashMap<>(), new HashMap<>(),
                 new DefaultEventBroadcaster());
         PDFLogicalStructureHandler handler = setUpPDFLogicalStructureHandler();
         StructureTreeMerger merger = new StructureTreeMerger(elem, handler, adapter, srcPage);
         merger.copyStructure(markedContentParents);
         PDFArray array = handler.getPageParentTree();
         PDFStructElem parentElem = (PDFStructElem)array.get(1);
         PDFDictionary objrDict = (PDFDictionary) parentElem.getKids().get(1);
         Assert.assertNull(objrDict.get("Obj"));
         doc.close();
     }

     @Test
     public void testDirectDescedants() throws IOException {
         PDFStructElem elem = new PDFStructElem();
         elem.setObjectNumber(100);
         adapter = new PDFBoxAdapter(pdfPage, new HashMap<>(), new HashMap<>(), new HashMap<>(), new HashMap<>(),
                 new DefaultEventBroadcaster());
         PDFLogicalStructureHandler handler = setUpPDFLogicalStructureHandler();
         PDPage srcPage = new PDPage();
         StructureTreeMerger merger = new StructureTreeMerger(elem, handler, adapter, srcPage);
         COSArray array = new COSArray();
         COSDictionary dict = new COSDictionary();
         dict.setItem(COSName.S, COSName.P);
         COSObject obj = new COSObject(dict);
 //        obj.setObjectNumber(200);
 //        obj.setGenerationNumber(0);
         array.add(0, obj);
         merger.createDirectDescendants(array, elem);
         List<PDFObject> list = elem.getKids();
         PDFStructElem kid = (PDFStructElem)list.get(0);
         PDFName name = (PDFName)kid.get("S");
         String test = name.getName();
         assertEquals(test, "P");
     }

     @Test
     public void testEmptyDict() throws IOException {
         adapter = new PDFBoxAdapter(pdfPage, new HashMap<>(), new HashMap<>(), new HashMap<>(), new HashMap<>(),
                 new DefaultEventBroadcaster());
         StructureTreeMerger structureTreeMerger = new StructureTreeMerger(null, null, adapter, null);
         COSArray cosArray = new COSArray();
         COSObject o = new COSObject(new COSDictionary());
 //        o.setObjectNumber(1);
 //        o.setGenerationNumber(1);
         cosArray.add(o);
         structureTreeMerger.copyStructure(cosArray);
         structureTreeMerger.addToPageParentTreeArray();
     }

     @Test
     public void testNonEmptyElement() {
         PDFStructElem sectElem = createPDFStructElem(StandardStructureTypes.Grouping.SECT, CONTENT);
         PDFStructElem partElem = createPDFStructElem(StandardStructureTypes.Paragraphlike.P, CONTENT);
         defaultTestSetCurrentSessionElem(Arrays.asList(sectElem, partElem), null, partElem,
                 "If element is not empty, it must be chosen");
     }

     @Test
     public void testEmptyElement() {
         PDFStructElem sectElem = createPDFStructElem(StandardStructureTypes.Grouping.SECT, CONTENT);
         PDFStructElem partElem = createPDFStructElem(StandardStructureTypes.Paragraphlike.P, null);
         defaultTestSetCurrentSessionElem(Arrays.asList(sectElem, partElem), null, sectElem,
                 "If element is empty, it must not be chosen");
     }

     @Test
     public void testSectElement() {
         PDFStructElem partElem = createPDFStructElem(StandardStructureTypes.Paragraphlike.P, CONTENT);
         PDFStructElem sectElem = createPDFStructElem(StandardStructureTypes.Grouping.SECT, CONTENT);
         defaultTestSetCurrentSessionElem(Arrays.asList(partElem, sectElem), null, sectElem,
                 "Must pick the first non empty element, back to front, it finds.");
     }

     @Test
     public void testEmptySectElement() {
         PDFStructElem partElem = createPDFStructElem(StandardStructureTypes.Paragraphlike.P, CONTENT);
         PDFStructElem sectElem = createPDFStructElem(StandardStructureTypes.Grouping.SECT, null);
         defaultTestSetCurrentSessionElem(Arrays.asList(partElem, sectElem), null, partElem,
                 "Elements can't be empty");
     }

     @Test
     public void testSetterReplacesPreviousValueIfEmpty() {
         PDFStructElem partElem = createPDFStructElem(StandardStructureTypes.Paragraphlike.P, CONTENT);
         PDFStructElem sectElem = createPDFStructElem(StandardStructureTypes.Grouping.SECT, null);
         defaultTestSetCurrentSessionElem(Arrays.asList(partElem, sectElem), Arrays.asList(sectElem, partElem),
                 partElem, "If the current session elem is empty, it must be replaced");
     }

     @Test
     public void testSetterDoesntReplacePreviousValueIfNotEmpty() {
         PDFStructElem partElem = createPDFStructElem(StandardStructureTypes.Paragraphlike.P, CONTENT);
         PDFStructElem sectElem = createPDFStructElem(StandardStructureTypes.Grouping.SECT, CONTENT);
         defaultTestSetCurrentSessionElem(Arrays.asList(partElem, sectElem), Arrays.asList(sectElem, partElem),
                 sectElem, "Elements can't be empty");
     }

     private void defaultTestSetCurrentSessionElem(List<PDFStructElem> elems, List<PDFStructElem> secondElems,
                                                   PDFStructElem expected, String assertionMessage) {
         PDFDocument mockPdfDoc = mock(PDFDocument.class);
         when(mockPdfDoc.getStructureTreeElements()).thenReturn(elems);
         PDFPage page = new PDFPage(new PDFResources(mockPdfDoc), 0, new Rectangle(), new Rectangle(),
                 new Rectangle(), new Rectangle());
         page.setDocument(mockPdfDoc);
         PDFBoxAdapter mockAdapter = mock(PDFBoxAdapter.class);
         when(mockAdapter.getTargetPage()).thenReturn(page);
         StructureTreeMerger structureTreeMerger = new StructureTreeMerger(null, null,
                 mockAdapter, null);
         structureTreeMerger.setCurrentSessionElem();
         assertEquals(assertionMessage, expected, structureTreeMerger.getCurrentSessionElem());
         if (secondElems != null) {
             when(mockPdfDoc.getStructureTreeElements()).thenReturn(elems);
             structureTreeMerger.setCurrentSessionElem();
             assertEquals(assertionMessage, expected, structureTreeMerger.getCurrentSessionElem());
         }
     }

     private PDFStructElem createPDFStructElem(StructureType type, String entry) {
         PDFStructElem elem = new PDFStructElem(null, type);
         elem.put("P", entry);
         return elem;
     }
 }
	/*
	* 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.fop.render.pdf;

	import java.awt.Rectangle;
	import java.awt.geom.Rectangle2D;
	import java.io.IOException;
	import java.util.Arrays;
	import java.util.HashMap;
	import java.util.List;

	import org.junit.Assert;
	import org.junit.Before;
	import org.junit.Test;

	import static org.junit.Assert.assertEquals;
	import static org.mockito.Mockito.mock;
	import static org.mockito.Mockito.when;

	import org.apache.pdfbox.cos.COSArray;
	import org.apache.pdfbox.cos.COSDictionary;
	import org.apache.pdfbox.cos.COSName;
	import org.apache.pdfbox.cos.COSObject;

	import org.apache.pdfbox.pdmodel.PDDocument;
	import org.apache.pdfbox.pdmodel.PDPage;

	import org.apache.fop.events.DefaultEventBroadcaster;

	import org.apache.fop.pdf.PDFArray;
	import org.apache.fop.pdf.PDFDictionary;
	import org.apache.fop.pdf.PDFDocument;
	import org.apache.fop.pdf.PDFName;
	import org.apache.fop.pdf.PDFNumber;
	import org.apache.fop.pdf.PDFObject;
	import org.apache.fop.pdf.PDFPage;
	import org.apache.fop.pdf.PDFReference;
	import org.apache.fop.pdf.PDFResources;
	import org.apache.fop.pdf.PDFStructElem;
	import org.apache.fop.pdf.StandardStructureTypes;
	import org.apache.fop.pdf.StructureType;

	import org.apache.fop.render.pdf.pdfbox.PDFBoxAdapter;
	import org.apache.fop.render.pdf.pdfbox.PDFBoxAdapterTestCase;
	import org.apache.fop.render.pdf.pdfbox.PageParentTreeFinder;
	import org.apache.fop.render.pdf.pdfbox.StructureTreeMerger;

	public class StructureTreeMergerTestCase {
	private static final String LINK = "linkTagged.pdf";
	private static final String BrokenLink = "brokenLink.pdf";
	private static final String MissingOBJR = "missingOBJR.pdf";
	private static final String CONTENT = "content";

	private PDFPage pdfPage;
	private PDFDocument pdfDoc;
	private PDFBoxAdapter adapter;

	@Test
	public void testCopyStructure() throws IOException {
	PDDocument doc = PDFBoxAdapterTestCase.load(LINK);
	PDPage srcPage = doc.getPage(0);
	PageParentTreeFinder finder = new PageParentTreeFinder(srcPage);
	COSArray markedContentParents = finder.getPageParentTreeArray(doc);
	PDFStructElem elem = new PDFStructElem();
	elem.setObjectNumber(2);
	adapter = new PDFBoxAdapter(pdfPage, new HashMap<>(), new HashMap<>(), new HashMap<>(), new HashMap<>(),
	new DefaultEventBroadcaster());
	adapter.setCurrentMCID(1);
	PDFLogicalStructureHandler handler = setUpPDFLogicalStructureHandler();
	StructureTreeMerger merger = new StructureTreeMerger(elem, handler, adapter, srcPage);
	merger.copyStructure(markedContentParents);
	PDFArray array = handler.getPageParentTree();
	checkMarkedContentsParentsForLinkTest(array);
	PDFStructElem first = (PDFStructElem)array.get(0);
	checkParentForLinkTest(first, 0);
	doc.close();
	}

	@Test
	public void testNullEntriesInParentTree() throws IOException {
	PDDocument doc = PDFBoxAdapterTestCase.load(LINK);
	PDPage srcPage = doc.getPage(0);
	PageParentTreeFinder finder = new PageParentTreeFinder(srcPage);
	COSArray markedContentParents = finder.getPageParentTreeArray(doc);
	markedContentParents.add(0, null);
	PDFStructElem elem = new PDFStructElem();
	elem.setObjectNumber(2);
	adapter = new PDFBoxAdapter(pdfPage, new HashMap<>(), new HashMap<>(), new HashMap<>(), new HashMap<>(),
	new DefaultEventBroadcaster());
	PDFLogicalStructureHandler handler = setUpPDFLogicalStructureHandler();
	StructureTreeMerger merger = new StructureTreeMerger(elem, handler, adapter, srcPage);
	merger.copyStructure(markedContentParents);
	PDFArray array = handler.getPageParentTree();
	Assert.assertNull(array.get(0));
	doc.close();
	}

	@Test
	public void testOBJRCorrectPosition() throws IOException {
	PDDocument doc = PDFBoxAdapterTestCase.load(MissingOBJR);
	PDPage srcPage = doc.getPage(0);
	PageParentTreeFinder finder = new PageParentTreeFinder(srcPage);
	COSArray markedContentParents = finder.getPageParentTreeArray(doc);
	PDFStructElem elem = new PDFStructElem();
	elem.setObjectNumber(2);
	adapter = new PDFBoxAdapter(pdfPage, new HashMap<>(), new HashMap<>(), new HashMap<>(), new HashMap<>(),
	new DefaultEventBroadcaster());
	PDFLogicalStructureHandler handler = setUpPDFLogicalStructureHandler();
	StructureTreeMerger merger = new StructureTreeMerger(elem, handler, adapter, srcPage);
	merger.copyStructure(markedContentParents);
	doc.close();
	// PDFArray array = handler.getPageParentTree();

	// PDFStructElem kid = (PDFStructElem)array.get(0);
	// PDFReference reference = (PDFReference) kid.get("P");
	// PDFStructElem parent = (PDFStructElem)reference.getObject();
	// List<PDFObject> kids = parent.getKids();
	// PDFDictionary first = (PDFDictionary) kids.get(0);

	// Assert.assertEquals(first.get("Type").toString(), "/OBJR");
	// PDFDictionary last = (PDFDictionary) kids.get(2);
	// Assert.assertEquals(last.get("Type").toString(), "/OBJR");

	// PDFStructElem middle = (PDFStructElem) kids.get(1);
	// Assert.assertEquals(middle.get("Type").toString(), "/StructElem");
	}

	private void checkMarkedContentsParentsForLinkTest(PDFArray array) {
	PDFStructElem first = (PDFStructElem)array.get(0);
	List<PDFObject> firstKids = first.getKids();
	PDFDictionary firstKid = (PDFDictionary) firstKids.get(0);
	int test = ((PDFNumber)firstKid.get("MCID")).getNumber().intValue();
	int expected = 1;
	assertEquals(test, expected);
	PDFDictionary firstKidSibling = (PDFDictionary) firstKids.get(2);
	test = ((PDFNumber)firstKidSibling.get("MCID")).getNumber().intValue();
	expected = 3;
	assertEquals(test, expected);
	PDFStructElem second = (PDFStructElem)array.get(1);
	List<PDFObject> secondKids = second.getKids();
	PDFDictionary secKid = (PDFDictionary) secondKids.get(0);
	test = ((PDFNumber)secKid.get("MCID")).getNumber().intValue();
	expected = 2;
	assertEquals(test, expected);
	}

	private void checkParentForLinkTest(PDFStructElem elem, int index) {
	String [] types = {"Sect"};
	PDFStructElem parent = (PDFStructElem)((PDFReference)elem.get("P")).getObject();
	if (index < types.length) {
	String test = ((PDFName)parent.get("S")).getName();
	String expected = types[index];
	assertEquals(test, expected);
	index++;
	checkParentForLinkTest(parent, index);
	}
	}

	@Before
	public void setUp() {
	Rectangle2D r = new Rectangle2D.Double();
	pdfDoc = new PDFDocument(" ");
	pdfPage = new PDFPage(new PDFResources(pdfDoc), 0, r, r, r, r);
	pdfDoc.makeStructTreeRoot(null);
	pdfPage.setObjectNumber(1);
	pdfPage.setDocument(pdfDoc);
	}

	private PDFLogicalStructureHandler setUpPDFLogicalStructureHandler() {
	PDFLogicalStructureHandler handler = new PDFLogicalStructureHandler(pdfDoc);
	handler.getParentTree().setDocument(pdfDoc);
	handler.startPage(pdfPage);
	return handler;
	}

	@Test
	public void testCheckNullCOSObject() throws IOException {
	PDDocument doc = PDFBoxAdapterTestCase.load(BrokenLink);
	PDPage srcPage = doc.getPage(0);
	PageParentTreeFinder finder = new PageParentTreeFinder(srcPage);
	COSArray markedContentParents = finder.getPageParentTreeArray(doc);
	COSObject nullObj = new COSObject(null);
	// nullObj.setObjectNumber(100);
	// nullObj.setGenerationNumber(0);
	PDFStructElem elem = new PDFStructElem();
	elem.setObjectNumber(2);
	COSObject parent = (COSObject)markedContentParents.get(1);
	COSDictionary dict = (COSDictionary) parent.getObject();
	COSArray kids = (COSArray) dict.getDictionaryObject(COSName.K);
	COSDictionary kid = (COSDictionary) kids.get(1);
	kid.setItem(COSName.OBJ, nullObj);
	adapter = new PDFBoxAdapter(pdfPage, new HashMap<>(), new HashMap<>(), new HashMap<>(), new HashMap<>(),
	new DefaultEventBroadcaster());
	PDFLogicalStructureHandler handler = setUpPDFLogicalStructureHandler();
	StructureTreeMerger merger = new StructureTreeMerger(elem, handler, adapter, srcPage);
	merger.copyStructure(markedContentParents);
	PDFArray array = handler.getPageParentTree();
	PDFStructElem parentElem = (PDFStructElem)array.get(1);
	PDFDictionary objrDict = (PDFDictionary) parentElem.getKids().get(1);
	Assert.assertNull(objrDict.get("Obj"));
	doc.close();
	}

	@Test
	public void testDirectDescedants() throws IOException {
	PDFStructElem elem = new PDFStructElem();
	elem.setObjectNumber(100);
	adapter = new PDFBoxAdapter(pdfPage, new HashMap<>(), new HashMap<>(), new HashMap<>(), new HashMap<>(),
	new DefaultEventBroadcaster());
	PDFLogicalStructureHandler handler = setUpPDFLogicalStructureHandler();
	PDPage srcPage = new PDPage();
	StructureTreeMerger merger = new StructureTreeMerger(elem, handler, adapter, srcPage);
	COSArray array = new COSArray();
	COSDictionary dict = new COSDictionary();
	dict.setItem(COSName.S, COSName.P);
	COSObject obj = new COSObject(dict);
	// obj.setObjectNumber(200);
	// obj.setGenerationNumber(0);
	array.add(0, obj);
	merger.createDirectDescendants(array, elem);
	List<PDFObject> list = elem.getKids();
	PDFStructElem kid = (PDFStructElem)list.get(0);
	PDFName name = (PDFName)kid.get("S");
	String test = name.getName();
	assertEquals(test, "P");
	}

	@Test
	public void testEmptyDict() throws IOException {
	adapter = new PDFBoxAdapter(pdfPage, new HashMap<>(), new HashMap<>(), new HashMap<>(), new HashMap<>(),
	new DefaultEventBroadcaster());
	StructureTreeMerger structureTreeMerger = new StructureTreeMerger(null, null, adapter, null);
	COSArray cosArray = new COSArray();
	COSObject o = new COSObject(new COSDictionary());
	// o.setObjectNumber(1);
	// o.setGenerationNumber(1);
	cosArray.add(o);
	structureTreeMerger.copyStructure(cosArray);
	structureTreeMerger.addToPageParentTreeArray();
	}

	@Test
	public void testNonEmptyElement() {
	PDFStructElem sectElem = createPDFStructElem(StandardStructureTypes.Grouping.SECT, CONTENT);
	PDFStructElem partElem = createPDFStructElem(StandardStructureTypes.Paragraphlike.P, CONTENT);
	defaultTestSetCurrentSessionElem(Arrays.asList(sectElem, partElem), null, partElem,
	"If element is not empty, it must be chosen");
	}

	@Test
	public void testEmptyElement() {
	PDFStructElem sectElem = createPDFStructElem(StandardStructureTypes.Grouping.SECT, CONTENT);
	PDFStructElem partElem = createPDFStructElem(StandardStructureTypes.Paragraphlike.P, null);
	defaultTestSetCurrentSessionElem(Arrays.asList(sectElem, partElem), null, sectElem,
	"If element is empty, it must not be chosen");
	}

	@Test
	public void testSectElement() {
	PDFStructElem partElem = createPDFStructElem(StandardStructureTypes.Paragraphlike.P, CONTENT);
	PDFStructElem sectElem = createPDFStructElem(StandardStructureTypes.Grouping.SECT, CONTENT);
	defaultTestSetCurrentSessionElem(Arrays.asList(partElem, sectElem), null, sectElem,
	"Must pick the first non empty element, back to front, it finds.");
	}

	@Test
	public void testEmptySectElement() {
	PDFStructElem partElem = createPDFStructElem(StandardStructureTypes.Paragraphlike.P, CONTENT);
	PDFStructElem sectElem = createPDFStructElem(StandardStructureTypes.Grouping.SECT, null);
	defaultTestSetCurrentSessionElem(Arrays.asList(partElem, sectElem), null, partElem,
	"Elements can't be empty");
	}

	@Test
	public void testSetterReplacesPreviousValueIfEmpty() {
	PDFStructElem partElem = createPDFStructElem(StandardStructureTypes.Paragraphlike.P, CONTENT);
	PDFStructElem sectElem = createPDFStructElem(StandardStructureTypes.Grouping.SECT, null);
	defaultTestSetCurrentSessionElem(Arrays.asList(partElem, sectElem), Arrays.asList(sectElem, partElem),
	partElem, "If the current session elem is empty, it must be replaced");
	}

	@Test
	public void testSetterDoesntReplacePreviousValueIfNotEmpty() {
	PDFStructElem partElem = createPDFStructElem(StandardStructureTypes.Paragraphlike.P, CONTENT);
	PDFStructElem sectElem = createPDFStructElem(StandardStructureTypes.Grouping.SECT, CONTENT);
	defaultTestSetCurrentSessionElem(Arrays.asList(partElem, sectElem), Arrays.asList(sectElem, partElem),
	sectElem, "Elements can't be empty");
	}

	private void defaultTestSetCurrentSessionElem(List<PDFStructElem> elems, List<PDFStructElem> secondElems,
	PDFStructElem expected, String assertionMessage) {
	PDFDocument mockPdfDoc = mock(PDFDocument.class);
	when(mockPdfDoc.getStructureTreeElements()).thenReturn(elems);
	PDFPage page = new PDFPage(new PDFResources(mockPdfDoc), 0, new Rectangle(), new Rectangle(),
	new Rectangle(), new Rectangle());
	page.setDocument(mockPdfDoc);
	PDFBoxAdapter mockAdapter = mock(PDFBoxAdapter.class);
	when(mockAdapter.getTargetPage()).thenReturn(page);
	StructureTreeMerger structureTreeMerger = new StructureTreeMerger(null, null,
	mockAdapter, null);
	structureTreeMerger.setCurrentSessionElem();
	assertEquals(assertionMessage, expected, structureTreeMerger.getCurrentSessionElem());
	if (secondElems != null) {
	when(mockPdfDoc.getStructureTreeElements()).thenReturn(elems);
	structureTreeMerger.setCurrentSessionElem();
	assertEquals(assertionMessage, expected, structureTreeMerger.getCurrentSessionElem());
	}
	}

	private PDFStructElem createPDFStructElem(StructureType type, String entry) {
	PDFStructElem elem = new PDFStructElem(null, type);
	elem.put("P", entry);
	return elem;
	}
	}