src/java/org/apache/fop/area/AreaTreeHandler.java - xmlgraphics-fop - Git at Google

 /*
  * Copyright 1999-2005 The Apache Software Foundation.
  *
  * Licensed 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.area;

 // Java
 import java.io.OutputStream;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 import java.util.HashMap;
 import java.util.Set;
 import java.util.HashSet;
 import java.util.Iterator;

 // XML
 import org.xml.sax.SAXException;

 // Apache
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.fop.apps.FOPException;
 import org.apache.fop.apps.FOUserAgent;
 import org.apache.fop.apps.FormattingResults;
 import org.apache.fop.fo.FOEventHandler;
 import org.apache.fop.fo.pagination.PageSequence;
 import org.apache.fop.fo.pagination.Root;
 import org.apache.fop.fo.pagination.bookmarks.BookmarkTree;
 import org.apache.fop.layoutmgr.PageSequenceLayoutManager;
 import org.apache.fop.layoutmgr.LayoutManagerMaker;
 import org.apache.fop.layoutmgr.LayoutManagerMapping;

 /**
  * Area tree handler for formatting objects.
  *
  * Concepts:
  * The area tree is to be as small as possible. With minimal classes
  * and data to fully represent an area tree for formatting objects.
  * The area tree needs to be simple to render and follow the spec
  * closely.
  * This area tree has the concept of page sequences.
  * Wherever possible information is discarded or optimized to
  * keep memory use low. The data is also organized to make it
  * possible for renderers to minimize their output.
  * A page can be saved if not fully resolved and once rendered
  * a page contains only size and id reference information.
  * The area tree pages are organized in a model that depends on the
  * type of renderer.
  */
 public class AreaTreeHandler extends FOEventHandler {

     // show statistics after document complete?
     private boolean outputStatistics;

     // for statistics gathering
     private Runtime runtime;

     // heap memory allocated (for statistics)
     private long initialMemory;

     // time used in rendering (for statistics)
     private long startTime;

     // the LayoutManager maker
     private LayoutManagerMaker lmMaker;

     // AreaTreeModel in use
     private AreaTreeModel model;

     // The fo:root node of the document
     private Root rootFObj;

     // HashMap of ID's whose area is located on one or more consecutive
     // PageViewports.  Each ID has an arraylist of PageViewports that
     // form the defined area of this ID
     private Map idLocations = new HashMap();

     // idref's whose target PageViewports have yet to be identified
     // Each idref has a HashSet of Resolvable objects containing that idref
     private Map unresolvedIDRefs = new HashMap();

      // The formatting results to be handed back to the caller.
     private FormattingResults results = new FormattingResults();

     private static Log log = LogFactory.getLog(AreaTreeHandler.class);

     /**
      * Constructor.
      * @param userAgent FOUserAgent object for process
      * @param renderType Desired fo.Constants output type (RENDER_PDF,
      *   RENDER_PS, etc.)
      * @param stream OutputStream
      * @throws FOPException if the RenderPagesModel cannot be created
      */
     public AreaTreeHandler (FOUserAgent userAgent, int renderType,
                 OutputStream stream) throws FOPException {
         super(userAgent);

         model = new RenderPagesModel(userAgent, renderType, fontInfo,
             stream);

         lmMaker = userAgent.getLayoutManagerMakerOverride();
         if (lmMaker == null) {
             lmMaker = new LayoutManagerMapping();
         }

         outputStatistics = log.isDebugEnabled();

         if (outputStatistics) {
             runtime = Runtime.getRuntime();
         }
     }

     /**
      * Get the area tree model for this area tree.
      *
      * @return AreaTreeModel the model being used for this area tree
      */
     public AreaTreeModel getAreaTreeModel() {
         return model;
     }

     /**
      * Get the LayoutManager maker for this area tree.
      *
      * @return LayoutManagerMaker the LayoutManager maker being used for this area tree
      */
     public LayoutManagerMaker getLayoutManagerMaker() {
         return lmMaker;
     }

     /**
      * Tie a PageViewport with an ID found on a child area of the PV.
      * Note that an area with a given ID may be on more than one PV, hence
      * an ID may have more than one PV associated with it.
      * @param id the property ID of the area
      * @param pv a page viewport that contains the area with this ID
      */
     public void associateIDWithPageViewport(String id, PageViewport pv) {
         if (log.isDebugEnabled()) {
             log.debug("associateIDWithPageViewport(" + id + ", " + pv + ")");
         }
         List pvList = (List) idLocations.get(id);
         if (pvList == null) { // first time ID located
             pvList = new ArrayList();
             idLocations.put(id, pvList);
             pvList.add(pv);

             /*
              * See if this ID is in the unresolved idref list, if so
              * resolve Resolvable objects tied to it.
              */
             tryIDResolution(id, pv, pvList);
         } else {
             pvList.add(pv);
         }
     }

     /**
      * Tries to resolve all unresolved ID references on the given page.
      * @param id ID to resolve
      * @param pv page viewport whose ID refs to resolve
      * @param List of PageViewports
      */
     private void tryIDResolution(String id, PageViewport pv, List pvList) {
         Set todo = (Set) unresolvedIDRefs.get(id);
         if (todo != null) {
             for (Iterator iter = todo.iterator(); iter.hasNext();) {
                 Resolvable res = (Resolvable) iter.next();
                 res.resolveIDRef(id, pvList);
             }
             unresolvedIDRefs.remove(id);
         }
     }

     /**
      * Tries to resolve all unresolved ID references on the given page.
      * @param pv page viewport whose ID refs to resolve
      */
     public void tryIDResolution(PageViewport pv) {
         String[] ids = pv.getIDRefs();
         if (ids != null) {
             for (int i = 0; i < ids.length; i++) {
                 List pvList = (List) idLocations.get(ids[i]);
                 if (pvList != null) {
                     tryIDResolution(ids[i], pv, pvList);
                 }
             }
         }
     }

     /**
      * Get the list of page viewports that have an area with a given id.
      * @param id the id to lookup
      * @return the list of PageViewports
      */
     public List getPageViewportsContainingID(String id) {
         return (List) idLocations.get(id);
     }

     /**
      * Get information about the rendered output, like
      * number of pages created.
      * @return the results structure
      */
     public FormattingResults getResults() {
         return this.results;
     }

     /**
      * Add an Resolvable object with an unresolved idref
      * @param idref the idref whose target id has not yet been located
      * @param res the Resolvable object needing the idref to be resolved
      */
     public void addUnresolvedIDRef(String idref, Resolvable res) {
         Set todo = (Set) unresolvedIDRefs.get(idref);
         if (todo == null) {
             todo = new HashSet();
             unresolvedIDRefs.put(idref, todo);
         }
         // add Resolvable object to this HashSet
         todo.add(res);
     }

     /**
      * Prepare AreaTreeHandler for document processing
      * This is called from FOTreeBuilder.startDocument()
      *
      * @throws SAXException if there is an error
      */
     public void startDocument() throws SAXException {
         //Initialize statistics
         if (outputStatistics) {
             initialMemory = runtime.totalMemory() - runtime.freeMemory();
             startTime = System.currentTimeMillis();
         }
     }

     /**
      * End the PageSequence.
      * The PageSequence formats Pages and adds them to the AreaTree.
      * The area tree then handles what happens with the pages.
      *
      * @param pageSequence the page sequence ending
      */
     public void endPageSequence(PageSequence pageSequence) {

         if (outputStatistics) {
             long memoryNow = runtime.totalMemory() - runtime.freeMemory();
             log.debug("Current heap size: " + (memoryNow / 1024L) + "Kb");
         }

         rootFObj = pageSequence.getRoot();

         // If no main flow, nothing to layout!
         if (pageSequence.getMainFlow() != null) {
             PageSequenceLayoutManager pageSLM;
             pageSLM = getLayoutManagerMaker().makePageSequenceLayoutManager(
                     this, pageSequence);
             pageSLM.activateLayout();
         }
     }

     public void notifyPageSequenceFinished(PageSequence pageSequence,
                                            int pageCount) {
         this.results.haveFormattedPageSequence(pageSequence,
                                                pageCount);
         if (log.isDebugEnabled()) {
             log.debug("Last page-sequence produced "
                     + pageCount + " pages.");
         }
     }

     /**
      * End the document.
      *
      * @throws SAXException if there is some error
      */
     public void endDocument() throws SAXException {

         // process fo:bookmark-tree
         BookmarkTree bookmarkTree = rootFObj.getBookmarkTree();
         if (bookmarkTree != null) {
             BookmarkData data = new BookmarkData(bookmarkTree);
             addOffDocumentItem(data);
         }

         model.endDocument();

         if (outputStatistics) {
             long memoryNow = runtime.totalMemory() - runtime.freeMemory();
             long memoryUsed = (memoryNow - initialMemory) / 1024L;
             long timeUsed = System.currentTimeMillis() - startTime;
             int pageCount = rootFObj.getTotalPagesGenerated();
             log.debug("Initial heap size: " + (initialMemory / 1024L) + "Kb");
             log.debug("Current heap size: " + (memoryNow / 1024L) + "Kb");
             log.debug("Total memory used: " + memoryUsed + "Kb");
             log.debug("Total time used: " + timeUsed + "ms");
             log.debug("Pages rendered: " + pageCount);
             if (pageCount > 0) {
                 long perPage = (timeUsed / pageCount);
                 long ppm = (timeUsed != 0 ? Math.round(60000 * pageCount / (double)timeUsed) : -1);
                 log.debug("Avg render time: " + perPage + "ms/page (" + ppm + "pages/min)");
             }
         }
     }

     /**
      * Add a OffDocumentItem to the area tree model
      * This checks if the OffDocumentItem is resolvable and attempts
      * to resolve or add the resolvable ids for later resolution.
      * @param odi the OffDocumentItem to add.
      */
     private void addOffDocumentItem(OffDocumentItem odi) {
         if (odi instanceof Resolvable) {
             Resolvable res = (Resolvable) odi;
             String[] ids = res.getIDRefs();
             for (int count = 0; count < ids.length; count++) {
                 if (idLocations.containsKey(ids[count])) {
                     res.resolveIDRef(ids[count], (List) idLocations.get(ids[count]));
                 } else {
                     log.warn(odi.getName() + ": Unresolved id reference \""
                         + ids[count] + "\" found.");
                     addUnresolvedIDRef(ids[count], res);
                 }
             }
             // check to see if ODI is now fully resolved, if so process it
             if (res.isResolved()) {
                 model.handleOffDocumentItem(odi);
             }
         } else {
             model.handleOffDocumentItem(odi);
         }
     }
 }
	/*
	* Copyright 1999-2005 The Apache Software Foundation.
	*
	* Licensed 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.area;

	// Java
	import java.io.OutputStream;
	import java.util.ArrayList;
	import java.util.List;
	import java.util.Map;
	import java.util.HashMap;
	import java.util.Set;
	import java.util.HashSet;
	import java.util.Iterator;

	// XML
	import org.xml.sax.SAXException;

	// Apache
	import org.apache.commons.logging.Log;
	import org.apache.commons.logging.LogFactory;
	import org.apache.fop.apps.FOPException;
	import org.apache.fop.apps.FOUserAgent;
	import org.apache.fop.apps.FormattingResults;
	import org.apache.fop.fo.FOEventHandler;
	import org.apache.fop.fo.pagination.PageSequence;
	import org.apache.fop.fo.pagination.Root;
	import org.apache.fop.fo.pagination.bookmarks.BookmarkTree;
	import org.apache.fop.layoutmgr.PageSequenceLayoutManager;
	import org.apache.fop.layoutmgr.LayoutManagerMaker;
	import org.apache.fop.layoutmgr.LayoutManagerMapping;

	/**
	* Area tree handler for formatting objects.
	*
	* Concepts:
	* The area tree is to be as small as possible. With minimal classes
	* and data to fully represent an area tree for formatting objects.
	* The area tree needs to be simple to render and follow the spec
	* closely.
	* This area tree has the concept of page sequences.
	* Wherever possible information is discarded or optimized to
	* keep memory use low. The data is also organized to make it
	* possible for renderers to minimize their output.
	* A page can be saved if not fully resolved and once rendered
	* a page contains only size and id reference information.
	* The area tree pages are organized in a model that depends on the
	* type of renderer.
	*/
	public class AreaTreeHandler extends FOEventHandler {

	// show statistics after document complete?
	private boolean outputStatistics;

	// for statistics gathering
	private Runtime runtime;

	// heap memory allocated (for statistics)
	private long initialMemory;

	// time used in rendering (for statistics)
	private long startTime;

	// the LayoutManager maker
	private LayoutManagerMaker lmMaker;

	// AreaTreeModel in use
	private AreaTreeModel model;

	// The fo:root node of the document
	private Root rootFObj;

	// HashMap of ID's whose area is located on one or more consecutive
	// PageViewports. Each ID has an arraylist of PageViewports that
	// form the defined area of this ID
	private Map idLocations = new HashMap();

	// idref's whose target PageViewports have yet to be identified
	// Each idref has a HashSet of Resolvable objects containing that idref
	private Map unresolvedIDRefs = new HashMap();

	// The formatting results to be handed back to the caller.
	private FormattingResults results = new FormattingResults();

	private static Log log = LogFactory.getLog(AreaTreeHandler.class);

	/**
	* Constructor.
	* @param userAgent FOUserAgent object for process
	* @param renderType Desired fo.Constants output type (RENDER_PDF,
	* RENDER_PS, etc.)
	* @param stream OutputStream
	* @throws FOPException if the RenderPagesModel cannot be created
	*/
	public AreaTreeHandler (FOUserAgent userAgent, int renderType,
	OutputStream stream) throws FOPException {
	super(userAgent);

	model = new RenderPagesModel(userAgent, renderType, fontInfo,
	stream);

	lmMaker = userAgent.getLayoutManagerMakerOverride();
	if (lmMaker == null) {
	lmMaker = new LayoutManagerMapping();
	}

	outputStatistics = log.isDebugEnabled();

	if (outputStatistics) {
	runtime = Runtime.getRuntime();
	}
	}

	/**
	* Get the area tree model for this area tree.
	*
	* @return AreaTreeModel the model being used for this area tree
	*/
	public AreaTreeModel getAreaTreeModel() {
	return model;
	}

	/**
	* Get the LayoutManager maker for this area tree.
	*
	* @return LayoutManagerMaker the LayoutManager maker being used for this area tree
	*/
	public LayoutManagerMaker getLayoutManagerMaker() {
	return lmMaker;
	}

	/**
	* Tie a PageViewport with an ID found on a child area of the PV.
	* Note that an area with a given ID may be on more than one PV, hence
	* an ID may have more than one PV associated with it.
	* @param id the property ID of the area
	* @param pv a page viewport that contains the area with this ID
	*/
	public void associateIDWithPageViewport(String id, PageViewport pv) {
	if (log.isDebugEnabled()) {
	log.debug("associateIDWithPageViewport(" + id + ", " + pv + ")");
	}
	List pvList = (List) idLocations.get(id);
	if (pvList == null) { // first time ID located
	pvList = new ArrayList();
	idLocations.put(id, pvList);
	pvList.add(pv);

	/*
	* See if this ID is in the unresolved idref list, if so
	* resolve Resolvable objects tied to it.
	*/
	tryIDResolution(id, pv, pvList);
	} else {
	pvList.add(pv);
	}
	}

	/**
	* Tries to resolve all unresolved ID references on the given page.
	* @param id ID to resolve
	* @param pv page viewport whose ID refs to resolve
	* @param List of PageViewports
	*/
	private void tryIDResolution(String id, PageViewport pv, List pvList) {
	Set todo = (Set) unresolvedIDRefs.get(id);
	if (todo != null) {
	for (Iterator iter = todo.iterator(); iter.hasNext();) {
	Resolvable res = (Resolvable) iter.next();
	res.resolveIDRef(id, pvList);
	}
	unresolvedIDRefs.remove(id);
	}
	}

	/**
	* Tries to resolve all unresolved ID references on the given page.
	* @param pv page viewport whose ID refs to resolve
	*/
	public void tryIDResolution(PageViewport pv) {
	String[] ids = pv.getIDRefs();
	if (ids != null) {
	for (int i = 0; i < ids.length; i++) {
	List pvList = (List) idLocations.get(ids[i]);
	if (pvList != null) {
	tryIDResolution(ids[i], pv, pvList);
	}
	}
	}
	}

	/**
	* Get the list of page viewports that have an area with a given id.
	* @param id the id to lookup
	* @return the list of PageViewports
	*/
	public List getPageViewportsContainingID(String id) {
	return (List) idLocations.get(id);
	}

	/**
	* Get information about the rendered output, like
	* number of pages created.
	* @return the results structure
	*/
	public FormattingResults getResults() {
	return this.results;
	}

	/**
	* Add an Resolvable object with an unresolved idref
	* @param idref the idref whose target id has not yet been located
	* @param res the Resolvable object needing the idref to be resolved
	*/
	public void addUnresolvedIDRef(String idref, Resolvable res) {
	Set todo = (Set) unresolvedIDRefs.get(idref);
	if (todo == null) {
	todo = new HashSet();
	unresolvedIDRefs.put(idref, todo);
	}
	// add Resolvable object to this HashSet
	todo.add(res);
	}

	/**
	* Prepare AreaTreeHandler for document processing
	* This is called from FOTreeBuilder.startDocument()
	*
	* @throws SAXException if there is an error
	*/
	public void startDocument() throws SAXException {
	//Initialize statistics
	if (outputStatistics) {
	initialMemory = runtime.totalMemory() - runtime.freeMemory();
	startTime = System.currentTimeMillis();
	}
	}

	/**
	* End the PageSequence.
	* The PageSequence formats Pages and adds them to the AreaTree.
	* The area tree then handles what happens with the pages.
	*
	* @param pageSequence the page sequence ending
	*/
	public void endPageSequence(PageSequence pageSequence) {

	if (outputStatistics) {
	long memoryNow = runtime.totalMemory() - runtime.freeMemory();
	log.debug("Current heap size: " + (memoryNow / 1024L) + "Kb");
	}

	rootFObj = pageSequence.getRoot();

	// If no main flow, nothing to layout!
	if (pageSequence.getMainFlow() != null) {
	PageSequenceLayoutManager pageSLM;
	pageSLM = getLayoutManagerMaker().makePageSequenceLayoutManager(
	this, pageSequence);
	pageSLM.activateLayout();
	}
	}

	public void notifyPageSequenceFinished(PageSequence pageSequence,
	int pageCount) {
	this.results.haveFormattedPageSequence(pageSequence,
	pageCount);
	if (log.isDebugEnabled()) {
	log.debug("Last page-sequence produced "
	+ pageCount + " pages.");
	}
	}

	/**
	* End the document.
	*
	* @throws SAXException if there is some error
	*/
	public void endDocument() throws SAXException {

	// process fo:bookmark-tree
	BookmarkTree bookmarkTree = rootFObj.getBookmarkTree();
	if (bookmarkTree != null) {
	BookmarkData data = new BookmarkData(bookmarkTree);
	addOffDocumentItem(data);
	}

	model.endDocument();

	if (outputStatistics) {
	long memoryNow = runtime.totalMemory() - runtime.freeMemory();
	long memoryUsed = (memoryNow - initialMemory) / 1024L;
	long timeUsed = System.currentTimeMillis() - startTime;
	int pageCount = rootFObj.getTotalPagesGenerated();
	log.debug("Initial heap size: " + (initialMemory / 1024L) + "Kb");
	log.debug("Current heap size: " + (memoryNow / 1024L) + "Kb");
	log.debug("Total memory used: " + memoryUsed + "Kb");
	log.debug("Total time used: " + timeUsed + "ms");
	log.debug("Pages rendered: " + pageCount);
	if (pageCount > 0) {
	long perPage = (timeUsed / pageCount);
	long ppm = (timeUsed != 0 ? Math.round(60000 * pageCount / (double)timeUsed) : -1);
	log.debug("Avg render time: " + perPage + "ms/page (" + ppm + "pages/min)");
	}
	}
	}

	/**
	* Add a OffDocumentItem to the area tree model
	* This checks if the OffDocumentItem is resolvable and attempts
	* to resolve or add the resolvable ids for later resolution.
	* @param odi the OffDocumentItem to add.
	*/
	private void addOffDocumentItem(OffDocumentItem odi) {
	if (odi instanceof Resolvable) {
	Resolvable res = (Resolvable) odi;
	String[] ids = res.getIDRefs();
	for (int count = 0; count < ids.length; count++) {
	if (idLocations.containsKey(ids[count])) {
	res.resolveIDRef(ids[count], (List) idLocations.get(ids[count]));
	} else {
	log.warn(odi.getName() + ": Unresolved id reference \""
	+ ids[count] + "\" found.");
	addUnresolvedIDRef(ids[count], res);
	}
	}
	// check to see if ODI is now fully resolved, if so process it
	if (res.isResolved()) {
	model.handleOffDocumentItem(odi);
	}
	} else {
	model.handleOffDocumentItem(odi);
	}
	}
	}