start of structure handler concept and adjusted the layout

handling appropriately


git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@194842 13f79535-47bb-0310-9956-ffa450edef68

12 files changed, 309 insertions, 118 deletions

diff --git a/src/org/apache/fop/apps/Driver.java b/src/org/apache/fop/apps/Driver.java
index e67443bcf..5c4d98c0f 100644
--- a/src/org/apache/fop/apps/Driver.java
+++ b/src/org/apache/fop/apps/Driver.java
@@ -453,11 +453,11 @@ public class Driver {
      * events but isn't a SAX Parser itself.
      */
     public ContentHandler getContentHandler() {
-        StreamRenderer streamRenderer = new StreamRenderer(_stream, _renderer);
-        streamRenderer.setLogger(getLogger());
+        StructureHandler handler = new LayoutHandler(_stream, _renderer, true);
+        handler.setLogger(getLogger());
         _treeBuilder.setLogger(getLogger());
         _treeBuilder.setUserAgent(getUserAgent());
-        _treeBuilder.setStreamRenderer(streamRenderer);
+        _treeBuilder.setStructHandler(handler);
 
         return _treeBuilder;
     }
diff --git a/src/org/apache/fop/apps/Fop.java b/src/org/apache/fop/apps/Fop.java
index 4dc42dcfb..7b170a7e2 100644
--- a/src/org/apache/fop/apps/Fop.java
+++ b/src/org/apache/fop/apps/Fop.java
@@ -17,8 +17,8 @@ public class Fop {
             Starter starter = options.getStarter();
             starter.run();
         } catch (FOPException e) {
-            if("null".equals(e.getMessage())) {
-                System.err.println("NullPointerException");
+            if("null".equals("" + e.getMessage())) {
+                System.err.println("Exception occured with a null error message");
             } else {
                 System.err.println("" + e.getMessage());
             }
diff --git a/src/org/apache/fop/apps/StreamRenderer.java b/src/org/apache/fop/apps/LayoutHandler.java
index 74c545360..ba4bdc04a 100644
--- a/src/org/apache/fop/apps/StreamRenderer.java
+++ b/src/org/apache/fop/apps/LayoutHandler.java
@@ -16,38 +16,32 @@ import org.apache.fop.fo.pagination.PageSequence;
 import org.apache.avalon.framework.logger.Logger;
 
 /**
-  This class acts as a bridge between the XML:FO parser
-  and the formatting/rendering classes. It will queue
-  PageSequences up until all the IDs required by them
-  are satisfied, at which time it will render the
-  pages.<P>
- 
-  StreamRenderer is created by Driver and called from
-  FOTreeBuilder when a PageSequence is created,
-  and AreaTree when a Page is formatted.<P>
-*/
-public class StreamRenderer {
+ * Layout handler that receives the structure events.
+ * This initiates layout processes and corresponding
+ * rendering processes such as start/end.
+ */
+public class LayoutHandler extends StructureHandler {
     private static final boolean MEM_PROFILE_WITH_GC = false;
 
     /**
       Somewhere to get our stats from.
-    */
+     */
     private Runtime runtime = Runtime.getRuntime();
 
     /**
       Keep track of the number of pages rendered.
-    */
+     */
     int pageCount = 0;
 
     /**
       Keep track of heap memory allocated,
       for statistical purposes.
-    */
+     */
     private long initialMemory;
 
     /**
       Keep track of time used by renderer.
-    */
+     */
     private long startTime;
 
     /**
@@ -55,34 +49,33 @@ public class StreamRenderer {
       written to. <B>Note</B> that some renderers
       do not render to a stream, and that this
       member can therefore be null.
-    */
+     */
     private OutputStream outputStream;
 
     /**
       The renderer being used.
-    */
+     */
     private Renderer renderer;
 
     /**
       The FontInfo for this renderer.
-    */
+     */
     private FontInfo fontInfo = new FontInfo();
 
     /**
-      The current set of id's in the FO tree
-      This is used so we know if the FO tree contains duplicates
-    */
-    private HashSet idReferences = new HashSet();
-
-    private Logger log;
-
-    /**
      * The current AreaTree for the PageSequence being rendered.
      */
     private AreaTree areaTree;
     private AreaTree.StorePagesModel atModel;
 
-    public StreamRenderer(OutputStream outputStream, Renderer renderer) {
+    /**
+     * @param outputStream the stream that the result is rendered to
+     * @param renderer the renderer to call
+     * @param store if true then use the store pages model and keep the
+     *              area tree in memory
+     */
+    public LayoutHandler(OutputStream outputStream, Renderer renderer,
+                         boolean store) {
         this.outputStream = outputStream;
         this.renderer = renderer;
 
@@ -91,24 +84,15 @@ public class StreamRenderer {
         areaTree.setTreeModel(atModel);
     }
 
-    public void setLogger(Logger logger) {
-        log = logger;
-    }
-
-    public HashSet getIDReferences() {
-        return idReferences;
-    }
-
     public AreaTree getAreaTree() {
         return areaTree;
     }
 
-    public void startRenderer()
-    throws SAXException {
+    public void startDocument() throws SAXException {
         pageCount = 0;
 
         if (MEM_PROFILE_WITH_GC)
-            System.gc();		// This takes time but gives better results
+            System.gc(); // This takes time but gives better results
 
         initialMemory = runtime.totalMemory() - runtime.freeMemory();
         startTime = System.currentTimeMillis();
@@ -121,15 +105,14 @@ public class StreamRenderer {
         }
     }
 
-    public void stopRenderer()
-    throws SAXException {
+    public void endDocument() throws SAXException {
         /*
-          Force the processing of any more queue elements,
-          even if they are not resolved.
-        */
+           Force the processing of any more queue elements,
+           even if they are not resolved.
+         */
         try {
             //processQueue(true);
-	    processAreaTree();
+            processAreaTree();
             renderer.stopRenderer();
         } catch (FOPException e) {
             throw new SAXException(e);
@@ -139,13 +122,13 @@ public class StreamRenderer {
         }
 
         if (MEM_PROFILE_WITH_GC)
-            System.gc();		// This takes time but gives better results
+            System.gc(); // This takes time but gives better results
 
         long memoryNow = runtime.totalMemory() - runtime.freeMemory();
         long memoryUsed = (memoryNow - initialMemory) / 1024L;
 
-        log.debug("Initial heap size: " + (initialMemory/1024L) + "Kb");
-        log.debug("Current heap size: " + (memoryNow/1024L) + "Kb");
+        log.debug("Initial heap size: " + (initialMemory / 1024L) + "Kb");
+        log.debug("Current heap size: " + (memoryNow / 1024L) + "Kb");
         log.debug("Total memory used: " + memoryUsed + "Kb");
 
         if (!MEM_PROFILE_WITH_GC) {
@@ -161,45 +144,46 @@ public class StreamRenderer {
     }
 
     /**
-      Format the PageSequence. The PageSequence
-      formats Pages and adds them to the AreaTree,
-      which subsequently calls the StreamRenderer
-      instance (this) again to render the page.
-      At this time the page might be printed
-      or it might be queued. A page might not
-      be renderable immediately if the IDReferences
-      are not all valid. In this case we defer
-      the rendering until they are all valid.
-    */
-    public void render(PageSequence pageSequence)
+       Format the PageSequence. The PageSequence
+       formats Pages and adds them to the AreaTree,
+       which subsequently calls the StreamRenderer
+       instance (this) again to render the page.
+       At this time the page might be printed
+       or it might be queued. A page might not
+       be renderable immediately if the IDReferences
+       are not all valid. In this case we defer
+       the rendering until they are all valid.
+     */
+    public void endPageSequence(PageSequence pageSequence)
     throws FOPException {
         //areaTree.setFontInfo(fontInfo);
 
-	pageSequence.format(areaTree);
+        pageSequence.format(areaTree);
     }
 
 
     private void processAreaTree() throws FOPException {
-	int count = 0;
-	int seqc = atModel.getPageSequenceCount();
-	while (count < seqc) {
-	    Title title = atModel.getTitle(count);
-	    renderer.startPageSequence(title);
-	    int pagec = atModel.getPageCount(count);
-	    for (int c=0; c < pagec; c++) {
-		try {
-		    renderer.renderPage(atModel.getPage(count, c));
-		} catch (java.io.IOException ioex) {
-		    throw new FOPException("I/O Error rendering page", ioex);
-		}
-	    }
-	    count++;
-	}
-	
+        int count = 0;
+        int seqc = atModel.getPageSequenceCount();
+        while (count < seqc) {
+            Title title = atModel.getTitle(count);
+            renderer.startPageSequence(title);
+            int pagec = atModel.getPageCount(count);
+            for (int c = 0; c < pagec; c++) {
+                try {
+                    renderer.renderPage(atModel.getPage(count, c));
+                } catch (java.io.IOException ioex) {
+                    throw new FOPException("I/O Error rendering page",
+                                           ioex);
+                }
+            }
+            count++;
+        }
+
     }
 
     public FontInfo getFontInfo() {
-	return this.fontInfo;
+        return this.fontInfo;
     }
 }
 
diff --git a/src/org/apache/fop/apps/StructureHandler.java b/src/org/apache/fop/apps/StructureHandler.java
new file mode 100644
index 000000000..3eb716331
--- /dev/null
+++ b/src/org/apache/fop/apps/StructureHandler.java
@@ -0,0 +1,219 @@
+/*
+ * $Id$
+ * Copyright (C) 2001 The Apache Software Foundation. All rights reserved.
+ * For details on use and redistribution please refer to the
+ * LICENSE file included with these sources.
+ */
+
+package org.apache.fop.apps;
+
+// Java
+import java.util.HashSet;
+
+import org.apache.avalon.framework.logger.Logger;
+import org.apache.fop.fo.pagination.PageSequence;
+import org.apache.fop.layout.FontInfo;
+
+import org.xml.sax.SAXException;
+
+/**
+ * This class receives structure events from the FO Tree.
+ * Sub-classes can then implement various methods to handle
+ * the FO Tree when the SAX events occur.
+ */
+public class StructureHandler {
+    /**
+       The current set of id's in the FO tree
+       This is used so we know if the FO tree contains duplicates
+     */
+    private HashSet idReferences = new HashSet();
+    protected Logger log;
+
+    public StructureHandler() {
+    }
+
+    public void setLogger(Logger logger) {
+        log = logger;
+    }
+
+    public HashSet getIDReferences() {
+        return idReferences;
+    }
+
+    public FontInfo getFontInfo() {
+        return null;
+    }
+
+    public void startDocument() throws SAXException {
+
+    }
+
+    public void endDocument() throws SAXException {
+
+    }
+
+    public void startPageSequence() {
+
+    }
+
+    public void endPageSequence(PageSequence pageSeq) throws FOPException {
+
+    }
+
+    public void setPageInfo() {
+
+    }
+
+    public void startBlock() {
+
+    }
+
+    public void endBlock() {
+
+    }
+
+
+    // Tables
+    public void startTable() {
+
+    }
+
+    public void endTable() {
+
+    }
+
+    public void startHeader() {
+
+    }
+
+    public void endHeader() {
+
+    }
+
+    public void startFooter() {
+
+    }
+
+    public void endFooter() {
+
+    }
+
+    public void startBody() {
+
+    }
+
+    public void endBody() {
+
+    }
+
+    public void startRow() {
+
+    }
+
+    public void endRow() {
+
+    }
+
+    public void startCell() {
+
+    }
+
+    public void endCell() {
+
+    }
+
+
+    // Lists
+    public void startList() {
+
+    }
+
+    public void endList() {
+
+    }
+
+    public void startListItem() {
+
+    }
+
+    public void endListItem() {
+
+    }
+
+    public void startListLabel() {
+
+    }
+
+    public void endListLabel() {
+
+    }
+
+    public void startListBody() {
+
+    }
+
+    public void endListBody() {
+
+    }
+
+
+    // Static Regions
+    public void startStatic() {
+
+    }
+
+    public void endStatic() {
+
+    }
+
+
+    public void startMarkup() {
+
+    }
+
+    public void endMarkup() {
+
+    }
+
+
+    public void startLink() {
+
+    }
+
+    public void endLink() {
+
+    }
+
+
+    public void image() {
+
+    }
+
+    public void pageRef() {
+
+    }
+
+    public void foreignObject() {
+
+    }
+
+    public void footnote() {
+
+    }
+
+    public void leader() {
+
+    }
+
+
+    public void characters() {
+
+    }
+
+    public void pageBreak() {
+
+    }
+
+
+}
+
diff --git a/src/org/apache/fop/extensions/Bookmarks.java b/src/org/apache/fop/extensions/Bookmarks.java
index 03ac929f6..4a4415ea0 100644
--- a/src/org/apache/fop/extensions/Bookmarks.java
+++ b/src/org/apache/fop/extensions/Bookmarks.java
@@ -7,6 +7,7 @@
 
 package org.apache.fop.extensions;
 
+import org.apache.fop.apps.LayoutHandler;
 import org.apache.fop.fo.FONode;
 import org.apache.fop.area.AreaTree;
 
@@ -40,8 +41,10 @@ public class Bookmarks extends ExtensionObj {
             data.addSubData(out.getData());
         }
         // add data to area tree for resolving and handling
-        AreaTree at = streamRenderer.getAreaTree();
-        at.addTreeExtension(data);
+        if(structHandler instanceof LayoutHandler) {
+            AreaTree at = ((LayoutHandler)structHandler).getAreaTree();
+            at.addTreeExtension(data);
+        }
     }
 }
 
diff --git a/src/org/apache/fop/fo/FONode.java b/src/org/apache/fop/fo/FONode.java
index 2e0dc72d8..ee0b6ad6a 100644
--- a/src/org/apache/fop/fo/FONode.java
+++ b/src/org/apache/fop/fo/FONode.java
@@ -9,7 +9,7 @@ package org.apache.fop.fo;
 
 // FOP
 import org.apache.fop.apps.FOPException;
-import org.apache.fop.apps.StreamRenderer;
+import org.apache.fop.apps.StructureHandler;
 import org.apache.fop.layout.Area;
 import org.apache.fop.util.CharUtilities;
 
@@ -48,7 +48,7 @@ abstract public class FONode {
         userAgent = ua;
     }
 
-    public void setStreamRenderer(StreamRenderer st) {
+    public void setStructHandler(StructureHandler st) {
     }
 
     public void handleAttrs(Attributes attlist) throws FOPException {
diff --git a/src/org/apache/fop/fo/FOTreeBuilder.java b/src/org/apache/fop/fo/FOTreeBuilder.java
index 988f7739f..946007d32 100644
--- a/src/org/apache/fop/fo/FOTreeBuilder.java
+++ b/src/org/apache/fop/fo/FOTreeBuilder.java
@@ -10,7 +10,7 @@ package org.apache.fop.fo;
 // FOP
 import org.apache.fop.layout.AreaTree;
 import org.apache.fop.apps.FOPException;
-import org.apache.fop.apps.StreamRenderer;
+import org.apache.fop.apps.StructureHandler;
 import org.apache.fop.fo.pagination.Root;
 import org.apache.fop.fo.pagination.PageSequence;
 import org.apache.fop.extensions.ExtensionObj;
@@ -70,7 +70,7 @@ public class FOTreeBuilder extends DefaultHandler {
      * The class that handles formatting and rendering to a stream
      * (mark-fop@inomial.com)
      */
-    private StreamRenderer streamRenderer;
+    private StructureHandler structHandler;
     private Logger log;
     private FOUserAgent userAgent;
 
@@ -89,8 +89,8 @@ public class FOTreeBuilder extends DefaultHandler {
     }
 
 
-    public void setStreamRenderer(StreamRenderer streamRenderer) {
-        this.streamRenderer = streamRenderer;
+    public void setStructHandler(StructureHandler sh) {
+        this.structHandler = sh;
     }
 
     /**
@@ -131,13 +131,13 @@ public class FOTreeBuilder extends DefaultHandler {
     throws SAXException {
         rootFObj = null;    // allows FOTreeBuilder to be reused
         log.info("building formatting object tree");
-        streamRenderer.startRenderer();
+        structHandler.startDocument();
     }
 
     public void endDocument()
     throws SAXException {
         log.info("Parsing of document complete, stopping renderer");
-        streamRenderer.stopRenderer();
+        structHandler.endDocument();
     }
 
     /**
@@ -185,7 +185,7 @@ public class FOTreeBuilder extends DefaultHandler {
             fobj.setUserAgent(userAgent);
             // set the stream renderer so that appropriate
             // elements can add pages and handle resolving references
-            fobj.setStreamRenderer(streamRenderer);
+            fobj.setStructHandler(structHandler);
 
             fobj.handleAttrs(attlist);
         } catch (FOPException e) {
@@ -209,7 +209,7 @@ public class FOTreeBuilder extends DefaultHandler {
     public void reset() {
         currentFObj = null;
         rootFObj = null;
-        streamRenderer = null;
+        structHandler = null;
     }
 
     public boolean hasData() {
diff --git a/src/org/apache/fop/fo/FObj.java b/src/org/apache/fop/fo/FObj.java
index 6e4219223..7be9fb522 100644
--- a/src/org/apache/fop/fo/FObj.java
+++ b/src/org/apache/fop/fo/FObj.java
@@ -11,7 +11,7 @@ package org.apache.fop.fo;
 import org.apache.fop.layout.Area;
 import org.apache.fop.layout.AreaClass;
 import org.apache.fop.apps.FOPException;
-import org.apache.fop.apps.StreamRenderer;
+import org.apache.fop.apps.StructureHandler;
 import org.apache.fop.layoutmgr.LayoutManager;
 import org.apache.fop.fo.properties.FOPropertyMapping;
 import org.apache.fop.layout.Area;
@@ -34,7 +34,7 @@ import java.util.HashSet;
  * base class for representation of formatting objects and their processing
  */
 public class FObj extends FONode {
-    protected StreamRenderer streamRenderer;
+    protected StructureHandler structHandler;
     public PropertyList properties;
     protected PropertyManager propMgr;
     protected String areaClass = AreaClass.UNASSIGNED;
@@ -135,8 +135,8 @@ public class FObj extends FONode {
         children.add(child);
     }
 
-    public void setStreamRenderer(StreamRenderer st) {
-        streamRenderer = st;
+    public void setStructHandler(StructureHandler st) {
+        structHandler = st;
     }
 
     /**
@@ -154,7 +154,7 @@ public class FObj extends FONode {
         if(prop != null) {
             String str = prop.getString();
             if(str != null && !str.equals("")) {
-                HashSet idrefs = streamRenderer.getIDReferences();
+                HashSet idrefs = structHandler.getIDReferences();
                 if(!idrefs.contains(str)) {
                     id = str;
                     idrefs.add(id);
diff --git a/src/org/apache/fop/fo/FObjMixed.java b/src/org/apache/fop/fo/FObjMixed.java
index a21732c1a..93cad8758 100644
--- a/src/org/apache/fop/fo/FObjMixed.java
+++ b/src/org/apache/fop/fo/FObjMixed.java
@@ -11,7 +11,7 @@ import org.apache.fop.layout.Area;
 import org.apache.fop.layout.FontState;
 import org.apache.fop.layout.FontInfo;
 import org.apache.fop.apps.FOPException;
-import org.apache.fop.apps.StreamRenderer;
+import org.apache.fop.apps.StructureHandler;
 import org.apache.fop.datatypes.ColorType;
 import org.apache.fop.layoutmgr.InlineStackingBPLayoutManager;
 import org.apache.fop.layoutmgr.LMiter;
@@ -30,7 +30,8 @@ public class FObjMixed extends FObj {
         super(parent);
     }
 
-    public void setStreamRenderer(StreamRenderer st) {
+    public void setStructHandler(StructureHandler st) {
+        super.setStructHandler(st);
         fontInfo = st.getFontInfo();
     }
 
diff --git a/src/org/apache/fop/fo/flow/Block.java b/src/org/apache/fop/fo/flow/Block.java
index 9fb9c9e83..5483ea685 100644
--- a/src/org/apache/fop/fo/flow/Block.java
+++ b/src/org/apache/fop/fo/flow/Block.java
@@ -16,7 +16,6 @@ import org.apache.fop.apps.FOPException;
 import org.apache.fop.layoutmgr.LayoutManager;
 import org.apache.fop.layoutmgr.BlockLayoutManager;
 import org.apache.fop.util.CharUtilities;
-import org.apache.fop.apps.StreamRenderer;
 
 import org.xml.sax.Attributes;
 
diff --git a/src/org/apache/fop/fo/pagination/PageSequence.java b/src/org/apache/fop/fo/pagination/PageSequence.java
index 591df45f7..3b75628cb 100644
--- a/src/org/apache/fop/fo/pagination/PageSequence.java
+++ b/src/org/apache/fop/fo/pagination/PageSequence.java
@@ -21,7 +21,6 @@ import org.apache.fop.layout.PageMaster;
 import org.apache.fop.area.AreaTree;
 import org.apache.fop.area.PageViewport;
 import org.apache.fop.apps.FOPException;
-import org.apache.fop.apps.StreamRenderer;
 
 import org.apache.fop.layoutmgr.PageLayoutManager;
 
@@ -48,11 +47,6 @@ public class PageSequence extends FObj {
     // associations
     //
     /**
-     * Use to layout and render the page sequence.
-     */
-    private StreamRenderer streamRenderer;
-
-    /**
      * The parent root object
      */
     private Root root;
@@ -271,14 +265,9 @@ public class PageSequence extends FObj {
 	}
     }
 
-
-    public void setStreamRenderer(StreamRenderer st) {
-	this.streamRenderer = st;
-    }
-
     public void end() {
 	try {
-	    this.streamRenderer.render(this);
+	    this.structHandler.endPageSequence(this);
 	} catch (FOPException fopex) {
 	    log.error("Error in PageSequence.end(): " +
 		      fopex.getMessage());
diff --git a/src/org/apache/fop/layout/AreaTree.java b/src/org/apache/fop/layout/AreaTree.java
index 234e77de9..12554efd0 100644
--- a/src/org/apache/fop/layout/AreaTree.java
+++ b/src/org/apache/fop/layout/AreaTree.java
@@ -9,7 +9,6 @@ package org.apache.fop.layout;
 
 // FOP
 import org.apache.fop.apps.FOPException;
-import org.apache.fop.apps.StreamRenderer;
 import org.apache.fop.fo.flow.StaticContent;
 import org.apache.fop.svg.*;
 import org.apache.fop.render.Renderer;
@@ -49,10 +48,7 @@ public class AreaTree {
      */
     Vector rootExtensions = null;
 
-    private StreamRenderer streamRenderer;
-
-    public AreaTree(StreamRenderer streamRenderer) {
-        this.streamRenderer = streamRenderer;
+    public AreaTree() {
     }
 
     public void setFontInfo(FontInfo fontInfo) {