fop-core/src/main/java/org/apache/fop/pdf/PDFStructElem.java - xmlgraphics-fop - 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.
  */

 /* $Id$ */

 package org.apache.fop.pdf;

 import java.io.IOException;
 import java.io.OutputStream;

 import java.io.Serializable;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Locale;

 import org.apache.fop.accessibility.StructureTreeElement;
 import org.apache.fop.pdf.StandardStructureAttributes.Table;
 import org.apache.fop.util.LanguageTags;

 /**
  * Class representing a PDF Structure Element.
  */
 public class PDFStructElem extends StructureHierarchyMember
         implements StructureTreeElement, CompressedObject, Serializable {

     private static final long serialVersionUID = -3055241807589202532L;
     private StructureType structureType;

     protected PDFStructElem parentElement;

     /**
      * Elements to be added to the kids array.
      */
     protected List<PDFObject> kids;

     private List<PDFDictionary> attributes;

     /**
      * Creates PDFStructElem with no entries.
      */
     public PDFStructElem() {
     }

     /**
      * Creates a new structure element.
      *
      * @param parent parent of this element
      * @param structureType the structure type of this element
      */
     public PDFStructElem(PDFObject parent, StructureType structureType) {
         this(parent);
         this.structureType = structureType;
         put("S", structureType.getName());
         setParent(parent);
     }

     private PDFStructElem(PDFObject parent) {
         if (parent instanceof PDFStructElem) {
             parentElement = (PDFStructElem) parent;
         }
     }

     /**
      * Returns the parent of this structure element.
      *
      * @return the parent, <code>null</code> if the parent is not a structure
      * element (i.e., is the structure tree root)
      */
     public PDFStructElem getParentStructElem() {
         return parentElement;
     }

     /** {@inheritDoc} */
     public void setParent(PDFObject parent) {
         if (parent != null && parent.hasObjectNumber()) {
            put("P", new PDFReference(parent));
         }
     }

     /**
      * Adds a kid to this structure element.
      *
      * @param kid element to be added
      */
     @Override
     public void addKid(PDFObject kid) {
         if (kids == null) {
             kids = new ArrayList<PDFObject>();
         }
         kids.add(kid);
     }

     /**
      * Sets the given mcid as the kid of this structure element. This element
      * will then add itself to its parent structure element if it has not
      * already, and so will the parent, and so on.
      *
      * @param mcid mcid of the marked-content sequence corresponding to this
      * structure element's kid
      */
     public void setMCIDKid(int mcid) {
         put("K", mcid);
     }

     /**
      * Sets the page reference of this structure element.
      *
      * @param page value for the Pg entry
      */
     public void setPage(PDFPage page) {
         put("Pg", page);
     }

     /**
      * Returns the structure type of this structure element.
      *
      * @return the value of the S entry
      */
     public StructureType getStructureType() {
         return structureType;
     }

     /**
      * Sets the language of this structure element.
      * @param language the language (as defined in the section about
      *                          "Natural Language Specification")
      */
     private void setLanguage(String language) {
         put("Lang", language);
     }

     /**
      * Sets the language of this structure element.
      *
      * @param language a value for the Lang entry
      */
     public void setLanguage(Locale language) {
         setLanguage(LanguageTags.toLanguageTag(language));
     }

     /**
      * Returns the language of this structure element.
      *
      * @return the value of the Lang entry (<code>null</code> if no language was specified)
      */
     public String getLanguage() {
         return (String) get("Lang");
     }

     @Override
     protected void writeDictionary(OutputStream out, StringBuilder textBuffer) throws IOException {
         attachKids();
         attachAttributes();
         super.writeDictionary(out, textBuffer);
     }

     private void attachAttributes() {
         if (attributes != null) {
             if (attributes.size() == 1) {
                 put("A", attributes.get(0));
             } else {
                 PDFArray array = new PDFArray(attributes);
                 put("A", array);
             }
         }
     }

     public void addKidInSpecificOrder(int position, PDFStructElem kid) {
         if (kids == null) {
             addKid(kid);
         } else {
             if ((kids.size() - 1) < position) {
                 kids.add(kid);
             } else if (kids.get(position) == null) {
                 kids.set(position, kid);
             } else {
                 if (!kids.contains(kid)) {
                     kids.add(position, kid);
                 }
             }
         }
     }

     /**
      * Attaches all valid kids to the kids array.
      *
      * @return true iff 1+ kids were added to the kids array
      */
     protected boolean attachKids() {
         List<PDFObject> validKids = new ArrayList<PDFObject>();
         if (kids != null) {
             for (PDFObject kid : kids) {
                 if (kid instanceof Placeholder)  {
                     if (((Placeholder) kid).attachKids()) {
                         validKids.add(kid);
                     }
                 } else {
                     validKids.add(kid);
                 }
             }
         }
         boolean kidsAttached = !validKids.isEmpty();
         if (kidsAttached) {
             PDFArray array = new PDFArray();
             for (PDFObject ob : validKids) {
                 array.add(ob);
             }
             put("K", array);
         }
         return kidsAttached;
     }

     public void setTableAttributeColSpan(int colSpan) {
         setTableAttributeRowColumnSpan("ColSpan", colSpan);
     }

     public void setTableAttributeRowSpan(int rowSpan) {
         setTableAttributeRowColumnSpan("RowSpan", rowSpan);
     }

     private void setTableAttributeRowColumnSpan(String typeSpan, int span) {
         PDFDictionary attribute = new PDFDictionary();
         attribute.put("O", Table.NAME);
         attribute.put(typeSpan, span);
         if (attributes == null) {
             attributes = new ArrayList<PDFDictionary>(2);
         }
         attributes.add(attribute);
     }

     public List<PDFObject> getKids() {
         return this.kids;
     }

     public int output(OutputStream stream) throws IOException {
         if (getDocument() != null && getDocument().getProfile().getPDFUAMode().isEnabled()) {
             if (entries.containsKey("Alt") && "".equals(get("Alt"))) {
                 put("Alt", "No alternate text specified");
             } else if (kids != null) {
                 for (PDFObject kid : kids) {
                     if (kid instanceof PDFStructElem
                             && !(kid instanceof Placeholder)
                             && structureType.toString().equals("P")
                             && isBSLE(((PDFStructElem) kid).getStructureType().toString())) {
                         structureType = StandardStructureTypes.Grouping.DIV;
                         put("S", StandardStructureTypes.Grouping.DIV.getName());
                         break;
                     }
                 }
             }
         }
         return super.output(stream);
     }

     private boolean isBSLE(String type) {
         String[] blseValues = {"Table", "L", "P"};
         return Arrays.asList(blseValues).contains(type);
     }

     /**
      * Class representing a placeholder for a PDF Structure Element.
      */
     public static class Placeholder extends PDFStructElem {

         private static final long serialVersionUID = -2397980642558372068L;

         @Override
         public void outputInline(OutputStream out, StringBuilder textBuffer) throws IOException {
             if (kids != null) {
                 assert kids.size() > 0;
                 for (int i = 0; i < kids.size(); i++) {
                     if (i > 0) {
                         textBuffer.append(' ');
                     }
                     Object obj = kids.get(i);
                     if (obj instanceof PDFStructElem) {
                         ((PDFStructElem) obj).setParent(parentElement);
                     }
                     formatObject(obj, out, textBuffer);
                 }
             }
         }

         public Placeholder(PDFObject parent) {
             super(parent);
         }
     }

 }
	/*
	* 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.
	*/

	/* $Id$ */

	package org.apache.fop.pdf;

	import java.io.IOException;
	import java.io.OutputStream;

	import java.io.Serializable;
	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.List;
	import java.util.Locale;

	import org.apache.fop.accessibility.StructureTreeElement;
	import org.apache.fop.pdf.StandardStructureAttributes.Table;
	import org.apache.fop.util.LanguageTags;

	/**
	* Class representing a PDF Structure Element.
	*/
	public class PDFStructElem extends StructureHierarchyMember
	implements StructureTreeElement, CompressedObject, Serializable {

	private static final long serialVersionUID = -3055241807589202532L;
	private StructureType structureType;

	protected PDFStructElem parentElement;

	/**
	* Elements to be added to the kids array.
	*/
	protected List<PDFObject> kids;

	private List<PDFDictionary> attributes;

	/**
	* Creates PDFStructElem with no entries.
	*/
	public PDFStructElem() {
	}

	/**
	* Creates a new structure element.
	*
	* @param parent parent of this element
	* @param structureType the structure type of this element
	*/
	public PDFStructElem(PDFObject parent, StructureType structureType) {
	this(parent);
	this.structureType = structureType;
	put("S", structureType.getName());
	setParent(parent);
	}

	private PDFStructElem(PDFObject parent) {
	if (parent instanceof PDFStructElem) {
	parentElement = (PDFStructElem) parent;
	}
	}

	/**
	* Returns the parent of this structure element.
	*
	* @return the parent, <code>null</code> if the parent is not a structure
	* element (i.e., is the structure tree root)
	*/
	public PDFStructElem getParentStructElem() {
	return parentElement;
	}

	/** {@inheritDoc} */
	public void setParent(PDFObject parent) {
	if (parent != null && parent.hasObjectNumber()) {
	put("P", new PDFReference(parent));
	}
	}

	/**
	* Adds a kid to this structure element.
	*
	* @param kid element to be added
	*/
	@Override
	public void addKid(PDFObject kid) {
	if (kids == null) {
	kids = new ArrayList<PDFObject>();
	}
	kids.add(kid);
	}

	/**
	* Sets the given mcid as the kid of this structure element. This element
	* will then add itself to its parent structure element if it has not
	* already, and so will the parent, and so on.
	*
	* @param mcid mcid of the marked-content sequence corresponding to this
	* structure element's kid
	*/
	public void setMCIDKid(int mcid) {
	put("K", mcid);
	}

	/**
	* Sets the page reference of this structure element.
	*
	* @param page value for the Pg entry
	*/
	public void setPage(PDFPage page) {
	put("Pg", page);
	}

	/**
	* Returns the structure type of this structure element.
	*
	* @return the value of the S entry
	*/
	public StructureType getStructureType() {
	return structureType;
	}

	/**
	* Sets the language of this structure element.
	* @param language the language (as defined in the section about
	* "Natural Language Specification")
	*/
	private void setLanguage(String language) {
	put("Lang", language);
	}

	/**
	* Sets the language of this structure element.
	*
	* @param language a value for the Lang entry
	*/
	public void setLanguage(Locale language) {
	setLanguage(LanguageTags.toLanguageTag(language));
	}

	/**
	* Returns the language of this structure element.
	*
	* @return the value of the Lang entry (<code>null</code> if no language was specified)
	*/
	public String getLanguage() {
	return (String) get("Lang");
	}

	@Override
	protected void writeDictionary(OutputStream out, StringBuilder textBuffer) throws IOException {
	attachKids();
	attachAttributes();
	super.writeDictionary(out, textBuffer);
	}

	private void attachAttributes() {
	if (attributes != null) {
	if (attributes.size() == 1) {
	put("A", attributes.get(0));
	} else {
	PDFArray array = new PDFArray(attributes);
	put("A", array);
	}
	}
	}

	public void addKidInSpecificOrder(int position, PDFStructElem kid) {
	if (kids == null) {
	addKid(kid);
	} else {
	if ((kids.size() - 1) < position) {
	kids.add(kid);
	} else if (kids.get(position) == null) {
	kids.set(position, kid);
	} else {
	if (!kids.contains(kid)) {
	kids.add(position, kid);
	}
	}
	}
	}

	/**
	* Attaches all valid kids to the kids array.
	*
	* @return true iff 1+ kids were added to the kids array
	*/
	protected boolean attachKids() {
	List<PDFObject> validKids = new ArrayList<PDFObject>();
	if (kids != null) {
	for (PDFObject kid : kids) {
	if (kid instanceof Placeholder) {
	if (((Placeholder) kid).attachKids()) {
	validKids.add(kid);
	}
	} else {
	validKids.add(kid);
	}
	}
	}
	boolean kidsAttached = !validKids.isEmpty();
	if (kidsAttached) {
	PDFArray array = new PDFArray();
	for (PDFObject ob : validKids) {
	array.add(ob);
	}
	put("K", array);
	}
	return kidsAttached;
	}

	public void setTableAttributeColSpan(int colSpan) {
	setTableAttributeRowColumnSpan("ColSpan", colSpan);
	}

	public void setTableAttributeRowSpan(int rowSpan) {
	setTableAttributeRowColumnSpan("RowSpan", rowSpan);
	}

	private void setTableAttributeRowColumnSpan(String typeSpan, int span) {
	PDFDictionary attribute = new PDFDictionary();
	attribute.put("O", Table.NAME);
	attribute.put(typeSpan, span);
	if (attributes == null) {
	attributes = new ArrayList<PDFDictionary>(2);
	}
	attributes.add(attribute);
	}

	public List<PDFObject> getKids() {
	return this.kids;
	}

	public int output(OutputStream stream) throws IOException {
	if (getDocument() != null && getDocument().getProfile().getPDFUAMode().isEnabled()) {
	if (entries.containsKey("Alt") && "".equals(get("Alt"))) {
	put("Alt", "No alternate text specified");
	} else if (kids != null) {
	for (PDFObject kid : kids) {
	if (kid instanceof PDFStructElem
	&& !(kid instanceof Placeholder)
	&& structureType.toString().equals("P")
	&& isBSLE(((PDFStructElem) kid).getStructureType().toString())) {
	structureType = StandardStructureTypes.Grouping.DIV;
	put("S", StandardStructureTypes.Grouping.DIV.getName());
	break;
	}
	}
	}
	}
	return super.output(stream);
	}

	private boolean isBSLE(String type) {
	String[] blseValues = {"Table", "L", "P"};
	return Arrays.asList(blseValues).contains(type);
	}

	/**
	* Class representing a placeholder for a PDF Structure Element.
	*/
	public static class Placeholder extends PDFStructElem {

	private static final long serialVersionUID = -2397980642558372068L;

	@Override
	public void outputInline(OutputStream out, StringBuilder textBuffer) throws IOException {
	if (kids != null) {
	assert kids.size() > 0;
	for (int i = 0; i < kids.size(); i++) {
	if (i > 0) {
	textBuffer.append(' ');
	}
	Object obj = kids.get(i);
	if (obj instanceof PDFStructElem) {
	((PDFStructElem) obj).setParent(parentElement);
	}
	formatObject(obj, out, textBuffer);
	}
	}
	}

	public Placeholder(PDFObject parent) {
	super(parent);
	}
	}

	}