When PDF accessibility is enabled, treat repeated table headings as artifacts

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@1362226 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/fop/layoutmgr/AbstractBreaker.java

@@ -329,7 +329,7 @@ public abstract class AbstractBreaker {
      * @return the top-level LayoutContext
      */
     protected LayoutContext createLayoutContext() {
-        return new LayoutContext(0);
+        return LayoutContext.newInstance();
     }
 
     /**
@@ -481,6 +481,11 @@ public abstract class AbstractBreaker {
         addAreas(alg, 0, partCount, originalList, effectiveList);
     }
 
+    protected void addAreas(PageBreakingAlgorithm alg, int startPart, int partCount,
+            BlockSequence originalList, BlockSequence effectiveList) {
+        addAreas(alg, startPart, partCount, originalList, effectiveList, LayoutContext.newInstance());
+    }
+
     /**
      * Phase 3 of Knuth algorithm: Adds the areas
      * @param alg PageBreakingAlgorithm instance which determined the breaks
@@ -490,8 +495,7 @@ public abstract class AbstractBreaker {
      * @param effectiveList effective Knuth element list (after adjustments)
      */
     protected void addAreas(PageBreakingAlgorithm alg, int startPart, int partCount,
-            BlockSequence originalList, BlockSequence effectiveList) {
-        LayoutContext childLC;
+            BlockSequence originalList, BlockSequence effectiveList, final LayoutContext childLC) {
         int startElementIndex = 0;
         int endElementIndex = 0;
         int lastBreak = -1;
@@ -566,7 +570,6 @@ public abstract class AbstractBreaker {
                     log.debug("     addAreas from " + startElementIndex
                             + " to " + endElementIndex);
                 }
-                childLC = new LayoutContext(0);
                 // set the space adjustment ratio
                 childLC.setSpaceAdjust(pbp.bpdAdjust);
                 // add space before if display-align is center or bottom

src/java/org/apache/fop/layoutmgr/AreaAdditionUtil.java

@@ -40,7 +40,7 @@ public final class AreaAdditionUtil {
     public static void addAreas(BlockStackingLayoutManager bslm,
             PositionIterator parentIter, LayoutContext layoutContext) {
         LayoutManager childLM;
-        LayoutContext lc = new LayoutContext(0);
+        LayoutContext lc = LayoutContext.offspringOf(layoutContext);
         LayoutManager firstLM = null;
         LayoutManager lastLM = null;
         Position firstPos = null;

src/java/org/apache/fop/layoutmgr/BlockContainerLayoutManager.java

@@ -193,7 +193,7 @@ public class BlockContainerLayoutManager extends BlockStackingLayoutManager impl
      */
     @Override
     protected LayoutContext makeChildLayoutContext(LayoutContext context) {
-        LayoutContext childLC = new LayoutContext(0);
+        LayoutContext childLC = LayoutContext.newInstance();
         childLC.setStackLimitBP(
                 context.getStackLimitBP().minus(MinOptMax.getInstance(relDims.bpd)));
         childLC.setRefIPD(relDims.ipd);
@@ -707,7 +707,7 @@ public class BlockContainerLayoutManager extends BlockStackingLayoutManager impl
             return curChildLM;
         }
 
-        public void addContainedAreas() {
+        public void addContainedAreas(LayoutContext layoutContext) {
             if (isEmpty()) {
                 return;
             }
@@ -715,8 +715,10 @@ public class BlockContainerLayoutManager extends BlockStackingLayoutManager impl
             //overflow should be visible.
             this.deferredAlg.removeAllPageBreaks();
             this.addAreas(this.deferredAlg,
+                          0,
                           this.deferredAlg.getPageBreaks().size(),
-                          this.deferredOriginalList, this.deferredEffectiveList);
+                          this.deferredOriginalList, this.deferredEffectiveList,
+                          LayoutContext.offspringOf(layoutContext));
         }
 
     }
@@ -754,7 +756,7 @@ public class BlockContainerLayoutManager extends BlockStackingLayoutManager impl
 
         LayoutManager childLM;
         LayoutManager lastLM = null;
-        LayoutContext lc = new LayoutContext(0);
+        LayoutContext lc = LayoutContext.offspringOf(layoutContext);
         lc.setSpaceAdjust(layoutContext.getSpaceAdjust());
         // set space after in the LayoutContext for children
         if (layoutContext.getSpaceAfter() > 0) {
@@ -821,7 +823,7 @@ public class BlockContainerLayoutManager extends BlockStackingLayoutManager impl
             }
         } else {
             //Add child areas inside the reference area
-            bcpos.getBreaker().addContainedAreas();
+            bcpos.getBreaker().addContainedAreas(layoutContext);
         }
 
         addMarkersToPage(false, isFirst(firstPos), isLast(lastPos));

src/java/org/apache/fop/layoutmgr/BlockLayoutManager.java

@@ -272,7 +272,7 @@ public class BlockLayoutManager extends BlockStackingLayoutManager implements Co
 
         LayoutManager childLM;
         LayoutManager lastLM = null;
-        LayoutContext lc = new LayoutContext(0);
+        LayoutContext lc = LayoutContext.offspringOf(layoutContext);
         lc.setSpaceAdjust(layoutContext.getSpaceAdjust());
         // set space after in the LayoutContext for children
         if (layoutContext.getSpaceAfter() > 0) {

src/java/org/apache/fop/layoutmgr/BlockStackingLayoutManager.java

@@ -383,7 +383,7 @@ public abstract class BlockStackingLayoutManager extends AbstractLayoutManager
      * @return a new child layout context
      */
     protected LayoutContext makeChildLayoutContext(LayoutContext context) {
-        LayoutContext childLC = new LayoutContext(0);
+        LayoutContext childLC = LayoutContext.newInstance();
         childLC.copyPendingMarksFrom(context);
         childLC.setStackLimitBP(context.getStackLimitBP());
         childLC.setRefIPD(referenceIPD);

src/java/org/apache/fop/layoutmgr/FlowLayoutManager.java

@@ -200,7 +200,7 @@ public class FlowLayoutManager extends BlockStackingLayoutManager
      */
     @Override
     protected LayoutContext makeChildLayoutContext(LayoutContext context) {
-        LayoutContext childLC = new LayoutContext(0);
+        LayoutContext childLC = LayoutContext.newInstance();
         childLC.setStackLimitBP(context.getStackLimitBP());
         childLC.setRefIPD(context.getRefIPD());
         childLC.setWritingMode(getCurrentPage().getSimplePageMaster().getWritingMode());

src/java/org/apache/fop/layoutmgr/FootnoteBodyLayoutManager.java

@@ -42,7 +42,7 @@ public class FootnoteBodyLayoutManager extends BlockStackingLayoutManager {
     public void addAreas(PositionIterator parentIter, LayoutContext layoutContext) {
         LayoutManager childLM;
         LayoutManager lastLM = null;
-        LayoutContext lc = new LayoutContext(0);
+        LayoutContext lc = LayoutContext.newInstance();
 
         // "unwrap" the NonLeafPositions stored in parentIter
         // and put them in a new list;

src/java/org/apache/fop/layoutmgr/LayoutContext.java

@@ -33,47 +33,27 @@ import org.apache.fop.traits.WritingMode;
  * This class is used to pass information to the getNextKnuthElements()
  * method. It is set up by higher level LM and used by lower level LM.
  */
-public class LayoutContext {
+public final class LayoutContext {
 
-    /**  linebreak at line feed only flag */
-    public static final int LINEBREAK_AT_LF_ONLY = 0x01;
     /** Generated break possibility is first in a new area */
-    public static final int NEW_AREA = 0x02;
-    /**  ipd unknown flag */
-    public static final int IPD_UNKNOWN = 0x04;
-    /** Signal to a Line LM that a higher level LM may provoke a change
-     *  in the reference area, thus ref area IPD. The LineLM should return
-     *  without looking for a line break.
-     */
-    public static final int CHECK_REF_AREA = 0x08;
+    public static final int NEW_AREA = 0x01;
 
     /**
      * If this flag is set, it indicates that any break-before values other than "auto" should
      * not cause a mandatory break as this break was already handled by a parent layout manager.
      */
-    public static final int SUPPRESS_BREAK_BEFORE = 0x10;
-    /** first area flag */
-    public static final int FIRST_AREA = 0x20;
-    /** try hypenate flag */
-    public static final int TRY_HYPHENATE = 0x40;
-    /** last area flag */
-    public static final int LAST_AREA = 0x80;
-    /**  resolve leading space flag */
-    public static final int RESOLVE_LEADING_SPACE = 0x100;
+    public static final int SUPPRESS_BREAK_BEFORE = 0x02;
 
-    /**
-     * This flag indicates that there's a keep-with-next that hasn't
-     * been processed, yet.
-     */
-    //public static final int KEEP_WITH_NEXT_PENDING = 0x200;
-    /**
-     * This flag indicates that there's a keep-with-previous that hasn't
-     * been processed, yet.
-     */
-    //public static final int KEEP_WITH_PREVIOUS_PENDING = 0x400;
+    public static final int FIRST_AREA = 0x04;
+
+    public static final int LAST_AREA = 0x08;
 
+    public static final int RESOLVE_LEADING_SPACE = 0x10;
+
+    private static final int TREAT_AS_ARTIFACT = 0x20;
 
     private int flags; // Contains some set of flags defined above
+
     /**
      * Total available stacking dimension for a "galley-level" layout
      * manager in block-progression-direction. It is passed by the
@@ -145,11 +125,27 @@ public class LayoutContext {
 
     private int disableColumnBalancing;
 
+    public static LayoutContext newInstance() {
+        return new LayoutContext(0);
+    }
+
+    public static LayoutContext copyOf(LayoutContext copy) {
+        return new LayoutContext(copy);
+    }
+
     /**
-     * Copy constructor for creating child layout contexts.
-     * @param parentLC the parent layout context to copy from
+     * Returns a descendant of the given layout context. The new context is the same as
+     * what would have been created by {@link #newInstance()}, except for inheritable
+     * properties that are passed on by the parent. At the moment, the only inheritable
+     * property is the value returned by {@link #treatAsArtifact()}.
      */
-    public LayoutContext(LayoutContext parentLC) {
+    public static LayoutContext offspringOf(LayoutContext parent) {
+        LayoutContext offspring = new LayoutContext(0);
+        offspring.setTreatAsArtifact(parent.treatAsArtifact());
+        return offspring;
+    }
+
+    private LayoutContext(LayoutContext parentLC) {
         this.flags = parentLC.flags;
         this.refIPD = parentLC.refIPD;
         this.writingMode = parentLC.writingMode;
@@ -170,11 +166,7 @@ public class LayoutContext {
         this.disableColumnBalancing = parentLC.disableColumnBalancing;
     }
 
-    /**
-     * Main constructor.
-     * @param flags the initial flags
-     */
-    public LayoutContext(int flags) {
+    private LayoutContext(int flags) {
         this.flags = flags;
         this.refIPD = 0;
         stackLimitBP = MinOptMax.ZERO;
@@ -435,11 +427,6 @@ public class LayoutContext {
         return hyphContext;
     }
 
-    /** @return true if try hyphenate is set */
-    public boolean tryHyphenate() {
-        return ((this.flags & TRY_HYPHENATE) != 0);
-    }
-
     /**
      * Sets the currently applicable alignment in BP direction.
      * @param alignment one of EN_START, EN_JUSTIFY etc.
@@ -673,7 +660,6 @@ public class LayoutContext {
         + "\nIs First Area: \t" + isFirstArea()
         + "\nStarts New Area: \t" + startsNewArea()
         + "\nIs Last Area: \t" + isLastArea()
-        + "\nTry Hyphenate: \t" + tryHyphenate()
         + "\nKeeps: \t[keep-with-next=" + getKeepWithNextPending()
                 + "][keep-with-previous=" + getKeepWithPreviousPending() + "] pending"
         + "\nBreaks: \tforced [" + (breakBefore != Constants.EN_AUTO ? "break-before" : "") + "]["
@@ -698,5 +684,13 @@ public class LayoutContext {
     public void setDisableColumnBalancing(int disableColumnBalancing) {
         this.disableColumnBalancing = disableColumnBalancing;
     }
+
+    public boolean treatAsArtifact() {
+        return (flags & TREAT_AS_ARTIFACT) != 0;
+    }
+
+    public void setTreatAsArtifact(boolean treatAsArtifact) {
+        setFlags(TREAT_AS_ARTIFACT, treatAsArtifact);
+    }
 }
 

src/java/org/apache/fop/layoutmgr/PageBreaker.java

@@ -167,7 +167,7 @@ public class PageBreaker extends AbstractBreaker {
                     && ((KnuthBlockBox) element).hasAnchors()) {
                     // element represents a line with footnote citations
                     containsFootnotes = true;
-                    LayoutContext footnoteContext = new LayoutContext(context);
+                    LayoutContext footnoteContext = LayoutContext.copyOf(context);
                     footnoteContext.setStackLimitBP(context.getStackLimitBP());
                     footnoteContext.setRefIPD(pslm.getCurrentPV()
                             .getRegionReference(Constants.FO_REGION_BODY).getIPD());
@@ -473,7 +473,7 @@ public class PageBreaker extends AbstractBreaker {
 
                 SpaceResolver.performConditionalsNotification(elementList,
                         firstIndex, lastIndex, -1);
-                LayoutContext childLC = new LayoutContext(0);
+                LayoutContext childLC = LayoutContext.newInstance();
                 AreaAdditionUtil.addAreas(null,
                         new KnuthPossPosIter(elementList, firstIndex, lastIndex + 1),
                         childLC);

src/java/org/apache/fop/layoutmgr/StaticContentLayoutManager.java

@@ -232,7 +232,7 @@ public class StaticContentLayoutManager extends BlockStackingLayoutManager {
             List returnList = new LinkedList();
 
             while ((curLM = getChildLM()) != null) {
-                LayoutContext childLC = new LayoutContext(0);
+                LayoutContext childLC = LayoutContext.newInstance();
                 childLC.setStackLimitBP(context.getStackLimitBP());
                 childLC.setRefIPD(context.getRefIPD());
                 childLC.setWritingMode(context.getWritingMode());

src/java/org/apache/fop/layoutmgr/inline/AbstractGraphicsLayoutManager.java

@@ -24,6 +24,7 @@ import java.awt.Rectangle;
 import java.util.List;
 
 import org.apache.fop.area.Area;
+import org.apache.fop.area.inline.InlineArea;
 import org.apache.fop.area.inline.InlineViewport;
 import org.apache.fop.datatypes.LengthBase;
 import org.apache.fop.fo.FObj;
@@ -92,7 +93,6 @@ public abstract class AbstractGraphicsLayoutManager extends LeafNodeLayoutManage
         transferForeignAttributes(viewportArea);
 
         InlineViewport vp = new InlineViewport(viewportArea, bidiLevel);
-        TraitSetter.addStructureTreeElement(vp, fobj.getStructureTreeElement());
         TraitSetter.setProducerID(vp, fobj.getId());
         vp.setIPD(imageLayout.getViewportSize().width);
         vp.setBPD(imageLayout.getViewportSize().height);
@@ -118,6 +118,21 @@ public abstract class AbstractGraphicsLayoutManager extends LeafNodeLayoutManage
         return super.getNextKnuthElements(context, alignment);
     }
 
+    @Override
+    protected InlineArea getEffectiveArea(LayoutContext layoutContext) {
+        /*
+         * If an image is in a repeated table heading, then it must be treated as real
+         * content the first time and then as artifact. Therefore we cannot re-use the
+         * area, as we have to account for the likely different values of treatAsArtifact.
+         */
+        InlineArea area = curArea != null ? curArea : getInlineArea();
+        curArea = null;
+        if (!layoutContext.treatAsArtifact()) {
+            TraitSetter.addStructureTreeElement(area, ((AbstractGraphics) fobj).getStructureTreeElement());
+        }
+        return area;
+    }
+
     /** {@inheritDoc} */
     protected AlignmentContext makeAlignmentContext(LayoutContext context) {
         final AbstractGraphics fobj = (AbstractGraphics)this.fobj;

src/java/org/apache/fop/layoutmgr/inline/AbstractPageNumberCitationLayoutManager.java

@@ -19,17 +19,18 @@
 
 package org.apache.fop.layoutmgr.inline;
 
-import org.apache.fop.area.Resolvable;
+import org.apache.fop.area.PageViewport;
 import org.apache.fop.area.Trait;
 import org.apache.fop.area.inline.InlineArea;
 import org.apache.fop.area.inline.TextArea;
+import org.apache.fop.area.inline.UnresolvedPageNumber;
 import org.apache.fop.fo.flow.AbstractPageNumberCitation;
 import org.apache.fop.fonts.Font;
 import org.apache.fop.fonts.FontInfo;
 import org.apache.fop.fonts.FontTriplet;
 import org.apache.fop.layoutmgr.LayoutContext;
-import org.apache.fop.layoutmgr.PositionIterator;
 import org.apache.fop.layoutmgr.TraitSetter;
+import org.apache.fop.traits.MinOptMax;
 
 /**
  * LayoutManager for the fo:page-number-citation(-last) formatting object
@@ -42,7 +43,9 @@ public abstract class AbstractPageNumberCitationLayoutManager extends LeafNodeLa
     protected Font font;
 
     /** Indicates whether the page referred to by the citation has been resolved yet */
-    protected boolean resolved = false;
+    private boolean resolved;
+
+    private String citationString;
 
     /**
      * Constructor
@@ -78,46 +81,78 @@ public abstract class AbstractPageNumberCitationLayoutManager extends LeafNodeLa
             );
     }
 
-    /** {@inheritDoc} */
-    public abstract InlineArea get(LayoutContext context);
+    @Override
+    protected MinOptMax getAllocationIPD(int refIPD) {
+        determineCitationString();
+        int ipd = getStringWidth(citationString);
+        return MinOptMax.getInstance(ipd);
+    }
 
-    /**
-     * {@inheritDoc}
-     *                                                                      , LayoutContext)
-     */
-    public void addAreas(PositionIterator posIter, LayoutContext context) {
-        super.addAreas(posIter, context);
-        if (!resolved) {
-            getPSLM().addUnresolvedArea(fobj.getRefId(), (Resolvable) curArea);
+    private void determineCitationString() {
+        assert citationString == null;
+        PageViewport page = getCitedPage();
+        if (page != null) {
+            resolved = true;
+            citationString = page.getPageNumberString();
+        } else {
+            resolved = false;
+            citationString = "MMM"; // Use a place holder
+        }
+    }
+
+    private int getStringWidth(String str) {
+        int width = 0;
+        for (int count = 0; count < str.length(); count++) {
+            width += font.getCharWidth(str.charAt(count));
+        }
+        return width;
+    }
+
+    protected abstract PageViewport getCitedPage();
+
+    @Override
+    protected InlineArea getEffectiveArea(LayoutContext layoutContext) {
+        InlineArea area = getPageNumberCitationArea();
+        if (!layoutContext.treatAsArtifact()) {
+            TraitSetter.addStructureTreeElement(area, fobj.getStructureTreeElement());
+        }
+        return area;
+    }
+
+    private InlineArea getPageNumberCitationArea() {
+        TextArea text;
+        if (resolved) {
+            text = new TextArea();
+            text.addWord(citationString, 0);
+        } else {
+            UnresolvedPageNumber unresolved = new UnresolvedPageNumber(fobj.getRefId(), font,
+                    getReferenceType());
+            getPSLM().addUnresolvedArea(fobj.getRefId(), unresolved);
+            text = unresolved;
         }
+        setTraits(text);
+        return text;
     }
 
     /**
-     * Updates the traits for the generated text area.
-     * @param text the text area
+     * @return {@link org.apache.fop.area.inline.UnresolvedPageNumber#FIRST} or
+     * {@linkorg.apache.fop.area.inline.UnresolvedPageNumber#LAST}
      */
-    protected void updateTextAreaTraits(TextArea text) {
+    protected abstract boolean getReferenceType();
+
+    private void setTraits(TextArea text) {
         TraitSetter.setProducerID(text, fobj.getId());
+        int bidiLevel = getBidiLevel();
+        text.setBidiLevel(bidiLevel);
+        int width = getStringWidth(citationString); // TODO: [GA] !I18N!
+        text.setIPD(width); // TODO: [GA] !I18N!
         text.setBPD(font.getAscender() - font.getDescender());
         text.setBaselineOffset(font.getAscender());
         TraitSetter.addFontTraits(text, font);
         text.addTrait(Trait.COLOR, fobj.getColor());
-        TraitSetter.addStructureTreeElement(text, fobj.getStructureTreeElement());
         TraitSetter.addTextDecoration(text, fobj.getTextDecoration());
     }
 
-    /**
-     * @param str string to be measured
-     * @return width (in millipoints ??) of the string
-     */
-    protected int getStringWidth(String str) {
-        int width = 0;
-        for (int count = 0; count < str.length(); count++) {
-            width += font.getCharWidth(str.charAt(count));
-        }
-        return width;
-    }
-
     /**
      * @return bidi level governing abstract page number citation
      */

src/java/org/apache/fop/layoutmgr/inline/CharacterLayoutManager.java

@@ -23,6 +23,7 @@ import java.util.LinkedList;
 import java.util.List;
 
 import org.apache.fop.area.Trait;
+import org.apache.fop.area.inline.InlineArea;
 import org.apache.fop.area.inline.TextArea;
 import org.apache.fop.fo.flow.Character;
 import org.apache.fop.fo.properties.CommonBorderPaddingBackground;
@@ -69,17 +70,15 @@ public class CharacterLayoutManager extends LeafNodeLayoutManager {
         hyphIPD = fobj.getCommonHyphenation().getHyphIPD(font);
         borderProps = fobj.getCommonBorderPaddingBackground();
         setCommonBorderPaddingBackground(borderProps);
-        TextArea chArea = getCharacterInlineArea(fobj);
-        chArea.setBaselineOffset(font.getAscender());
-        setCurrentArea(chArea);
     }
 
-    private TextArea getCharacterInlineArea(Character node) {
+    private TextArea createCharacterArea() {
+        Character fobj = (Character) this.fobj;
         TextArea text = new TextArea();
-        char ch = node.getCharacter();
+        char ch = fobj.getCharacter();
         int ipd = font.getCharWidth(ch);
         int blockProgressionOffset = 0;
-        int level = node.getBidiLevel();
+        int level = fobj.getBidiLevel();
         if (CharUtilities.isAnySpace(ch)) {
             // add space unless it's zero-width:
             if (!CharUtilities.isZeroWidthSpace(ch)) {
@@ -90,32 +89,29 @@ public class CharacterLayoutManager extends LeafNodeLayoutManager {
             int[] levels = ( level >= 0 ) ? new int[] {level} : null;
             text.addWord(String.valueOf(ch), ipd, null, levels, null, blockProgressionOffset);
         }
-        TraitSetter.setProducerID(text, node.getId());
-        TraitSetter.addTextDecoration(text, node.getTextDecoration());
-        TraitSetter.addStructureTreeElement(text, node.getStructureTreeElement());
+
+        TraitSetter.setProducerID(text, fobj.getId());
+        TraitSetter.addTextDecoration(text, fobj.getTextDecoration());
+        text.setIPD(font.getCharWidth(fobj.getCharacter()));
+        text.setBPD(font.getAscender() - font.getDescender());
+        text.setBaselineOffset(font.getAscender());
+        TraitSetter.addFontTraits(text, font);
+        text.addTrait(Trait.COLOR, fobj.getColor());
         return text;
     }
 
-    /** {@inheritDoc} */
     @Override
-    public List getNextKnuthElements(LayoutContext context, int alignment) {
-        MinOptMax ipd;
-        curArea = get(context);
-        KnuthSequence seq = new InlineKnuthSequence();
-
-        if (curArea == null) {
-            setFinished(true);
-            return null;
+    protected InlineArea getEffectiveArea(LayoutContext layoutContext) {
+        InlineArea area = createCharacterArea();
+        if (!layoutContext.treatAsArtifact()) {
+            TraitSetter.addStructureTreeElement(area, ((Character) fobj).getStructureTreeElement());
         }
+        return area;
+    }
 
-        Character fobj = (Character)this.fobj;
-
-        ipd = MinOptMax.getInstance(curArea.getIPD());
-
-        curArea.setBPD(font.getAscender() - font.getDescender());
-
-        TraitSetter.addFontTraits(curArea, font);
-        curArea.addTrait(Trait.COLOR, fobj.getColor());
+    /** {@inheritDoc} */
+    public List getNextKnuthElements(LayoutContext context, int alignment) {
+        Character fobj = (Character) this.fobj;
 
         // TODO: may need some special handling for fo:character
         alignmentContext = new AlignmentContext(font
@@ -126,9 +122,11 @@ public class CharacterLayoutManager extends LeafNodeLayoutManager {
                                     , fobj.getDominantBaseline()
                                     , context.getAlignmentContext());
 
+        KnuthSequence seq = new InlineKnuthSequence();
         addKnuthElementsForBorderPaddingStart(seq);
 
         // create the AreaInfo object to store the computed values
+        MinOptMax ipd = MinOptMax.getInstance(font.getCharWidth(fobj.getCharacter()));
         areaInfo = new AreaInfo((short) 0, ipd, false, alignmentContext);
 
         // node is a fo:Character
@@ -162,7 +160,7 @@ public class CharacterLayoutManager extends LeafNodeLayoutManager {
     /** {@inheritDoc} */
     @Override
     public String getWordChars(Position pos) {
-        return ((TextArea) curArea).getText();
+        return String.valueOf(((Character) fobj).getCharacter());
     }
 
     /** {@inheritDoc} */

src/java/org/apache/fop/layoutmgr/inline/ContentLayoutManager.java

@@ -110,7 +110,8 @@ public class ContentLayoutManager extends AbstractBaseLayoutManager
 
         int ipd = 1000000;
 
-        LayoutContext childLC = new LayoutContext(LayoutContext.NEW_AREA);
+        LayoutContext childLC = LayoutContext.newInstance();
+        childLC.setFlags(LayoutContext.NEW_AREA);
         childLC.setLeadingSpace(new SpaceSpecifier(false));
         childLC.setTrailingSpace(new SpaceSpecifier(false));
         childLC.setRefIPD(ipd);
@@ -143,7 +144,7 @@ public class ContentLayoutManager extends AbstractBaseLayoutManager
             middlefollow = maxtb - lineLead;
         }
 
-        LayoutContext lc = new LayoutContext(0);
+        LayoutContext lc = LayoutContext.newInstance();
 
         lc.setFlags(LayoutContext.RESOLVE_LEADING_SPACE, true);
         lc.setLeadingSpace(new SpaceSpecifier(false));
@@ -160,7 +161,7 @@ public class ContentLayoutManager extends AbstractBaseLayoutManager
         int savedIPD = ((InlineArea)holder).getIPD();
         // set to zero the ipd adjustment ratio, to avoid spaces in the pattern
         // to be modified
-        LayoutContext childContext = new LayoutContext(context);
+        LayoutContext childContext = LayoutContext.copyOf(context);
         childContext.setIPDAdjust(0.0);
         childLM.addAreas(posIter, childContext);
         ((InlineArea)holder).setIPD(savedIPD);

src/java/org/apache/fop/layoutmgr/inline/FootnoteLayoutManager.java

@@ -151,7 +151,7 @@ public class FootnoteLayoutManager extends InlineStackingLayoutManager {
         citationLM.setParent(getParent());
 
         // make the citationLM add its areas
-        LayoutContext childContext = new LayoutContext(context);
+        LayoutContext childContext = LayoutContext.copyOf(context);
         PositionIterator childPosIter = new PositionIterator(positionList.listIterator());
         LayoutManager childLM;
         while ((childLM = childPosIter.getNextChildLM()) != null) {

src/java/org/apache/fop/layoutmgr/inline/InlineLayoutManager.java

@@ -283,7 +283,7 @@ public class InlineLayoutManager extends InlineStackingLayoutManager {
                                     , context.getAlignmentContext());
         }
 
-        childLC = new LayoutContext(context);
+        childLC = LayoutContext.copyOf(context);
         childLC.setAlignmentContext(alignmentContext);
 
         if (context.startsNewArea()) {
@@ -439,7 +439,7 @@ public class InlineLayoutManager extends InlineStackingLayoutManager {
 
         addId();
 
-        setChildContext(new LayoutContext(context)); // Store current value
+        setChildContext(LayoutContext.copyOf(context)); // Store current value
 
         // "Unwrap" the NonLeafPositions stored in parentIter and put
         // them in a new list.  Set lastLM to be the LayoutManager

src/java/org/apache/fop/layoutmgr/inline/LeaderLayoutManager.java

@@ -191,7 +191,7 @@ public class LeaderLayoutManager extends LeafNodeLayoutManager {
             clm.addChildLM(lm);
             lm.initialize();
 
-            LayoutContext childContext = new LayoutContext(0);
+            LayoutContext childContext = LayoutContext.newInstance();
             childContext.setAlignmentContext(context.getAlignmentContext());
             contentList = clm.getNextKnuthElements(childContext, 0);
             int width = clm.getStackingSize();

src/java/org/apache/fop/layoutmgr/inline/LeafNodeLayoutManager.java

@@ -188,7 +188,7 @@ public abstract class LeafNodeLayoutManager extends AbstractLayoutManager
     public void addAreas(PositionIterator posIter, LayoutContext context) {
         addId();
 
-        InlineArea area = getEffectiveArea();
+        InlineArea area = getEffectiveArea(context);
         if (area.getAllocIPD() > 0 || area.getAllocBPD() > 0) {
             offsetArea(area, context);
             widthAdjustArea(area, context);
@@ -211,7 +211,7 @@ public abstract class LeafNodeLayoutManager extends AbstractLayoutManager
      * @return the effective area to be added to the area tree. Normally, this is simply "curArea"
      * but in the case of page-number(-citation) curArea is cloned, updated and returned.
      */
-    protected InlineArea getEffectiveArea() {
+    protected InlineArea getEffectiveArea(LayoutContext layoutContext) {
         return curArea;
     }
 
@@ -264,11 +264,6 @@ public abstract class LeafNodeLayoutManager extends AbstractLayoutManager
     public List getNextKnuthElements(LayoutContext context, int alignment) {
         curArea = get(context);
 
-        if (curArea == null) {
-            setFinished(true);
-            return null;
-        }
-
         alignmentContext = makeAlignmentContext(context);
 
         MinOptMax ipd = getAllocationIPD(context.getRefIPD());

src/java/org/apache/fop/layoutmgr/inline/LineLayoutManager.java

@@ -674,7 +674,7 @@ public class LineLayoutManager extends InlineStackingLayoutManager
      * @param context the LayoutContext
      */
     private void collectInlineKnuthElements(LayoutContext context) {
-        LayoutContext inlineLC = new LayoutContext(context);
+        LayoutContext inlineLC = LayoutContext.copyOf(context);
 
         // convert all the text in a sequence of paragraphs made
         // of KnuthBox, KnuthGlue and KnuthPenalty objects
@@ -1522,7 +1522,7 @@ public class LineLayoutManager extends InlineStackingLayoutManager
         PositionIterator inlinePosIter = new KnuthPossPosIter(seq, startElementIndex,
                 endElementIndex + 1);
 
-        LayoutContext lc = new LayoutContext(0);
+        LayoutContext lc = LayoutContext.offspringOf(context);
         lc.setAlignmentContext(alignmentContext);
         lc.setSpaceAdjust(lbp.dAdjust);
         lc.setIPDAdjust(lbp.ipdAdjust);
@@ -1577,12 +1577,12 @@ public class LineLayoutManager extends InlineStackingLayoutManager
 
         LineArea lineArea = new LineArea();
         setCurrentArea(lineArea);
-        LayoutContext lc = new LayoutContext(0);
+        LayoutContext lc = LayoutContext.newInstance();
         lc.setAlignmentContext(alignmentContext);
         setChildContext(lc);
 
         PositionIterator childPosIter = new PositionIterator(positionList.listIterator());
-        LayoutContext blocklc = new LayoutContext(0);
+        LayoutContext blocklc = LayoutContext.offspringOf(context);
         blocklc.setLeadingSpace(new SpaceSpecifier(true));
         blocklc.setTrailingSpace(new SpaceSpecifier(false));
         blocklc.setFlags(LayoutContext.RESOLVE_LEADING_SPACE, true);

src/java/org/apache/fop/layoutmgr/inline/PageNumberCitationLastLayoutManager.java

@@ -20,65 +20,36 @@
 package org.apache.fop.layoutmgr.inline;
 
 import org.apache.fop.area.PageViewport;
-import org.apache.fop.area.Resolvable;
-import org.apache.fop.area.inline.InlineArea;
-import org.apache.fop.area.inline.TextArea;
 import org.apache.fop.area.inline.UnresolvedPageNumber;
 import org.apache.fop.fo.flow.PageNumberCitationLast;
-import org.apache.fop.layoutmgr.LayoutContext;
-import org.apache.fop.layoutmgr.LayoutManager;
 
 /**
- * LayoutManager for the fo:page-number-citation-last formatting object
+ * LayoutManager for the fo:page-number-citation-last formatting object.
  */
 public class PageNumberCitationLastLayoutManager extends AbstractPageNumberCitationLayoutManager {
 
     /**
-     * Constructor
+     * Constructor.
      *
      * @param node the formatting object that creates this area
      * TODO better retrieval of font info
      */
     public PageNumberCitationLastLayoutManager(PageNumberCitationLast node) {
         super(node);
-        fobj = node;
     }
 
-    /** {@inheritDoc} */
-    public InlineArea get(LayoutContext context) {
-        curArea = getPageNumberCitationLastInlineArea(parentLayoutManager);
-        return curArea;
-    }
-
-    /**
-     * if id can be resolved then simply return a word, otherwise
-     * return a resolvable area
-     */
-    private InlineArea getPageNumberCitationLastInlineArea(LayoutManager parentLM) {
-        TextArea text = null;
-        int level = getBidiLevel();
-        if (!getPSLM().associateLayoutManagerID(fobj.getRefId())) {
-            text = new UnresolvedPageNumber(fobj.getRefId(), font, UnresolvedPageNumber.LAST);
-            getPSLM().addUnresolvedArea(fobj.getRefId(), (Resolvable)text);
-            String str = "MMM"; // reserve three spaces for page number
-            int width = getStringWidth(str);
-            text.setBidiLevel(level);
-            text.setIPD(width);
-            resolved = false;
+    @Override
+    protected PageViewport getCitedPage() {
+        if (getPSLM().associateLayoutManagerID(fobj.getRefId())) {
+            return getPSLM().getLastPVWithID(fobj.getRefId());
         } else {
-            PageViewport page = getPSLM().getLastPVWithID(fobj.getRefId());
-            String str = page.getPageNumberString();
-            // get page string from parent, build area
-            text = new TextArea();
-            int width = getStringWidth(str);
-            text.setBidiLevel(level);
-            text.addWord(str, 0, level);
-            text.setIPD(width);
-            resolved = true;
+            return null;
         }
+    }
 
-        updateTextAreaTraits(text);
-
-        return text;
+    @Override
+    protected boolean getReferenceType() {
+        return UnresolvedPageNumber.LAST;
     }
+
 }

src/java/org/apache/fop/layoutmgr/inline/PageNumberCitationLayoutManager.java

@@ -20,19 +20,16 @@
 package org.apache.fop.layoutmgr.inline;
 
 import org.apache.fop.area.PageViewport;
-import org.apache.fop.area.inline.InlineArea;
-import org.apache.fop.area.inline.TextArea;
 import org.apache.fop.area.inline.UnresolvedPageNumber;
 import org.apache.fop.fo.flow.PageNumberCitation;
-import org.apache.fop.layoutmgr.LayoutContext;
 
 /**
- * LayoutManager for the fo:page-number-citation formatting object
+ * LayoutManager for the fo:page-number-citation formatting object.
  */
 public class PageNumberCitationLayoutManager extends AbstractPageNumberCitationLayoutManager {
 
     /**
-     * Constructor
+     * Constructor.
      *
      * @param node the formatting object that creates this area
      * TODO better retrieval of font info
@@ -41,42 +38,14 @@ public class PageNumberCitationLayoutManager extends AbstractPageNumberCitationL
         super(node);
     }
 
-    /** {@inheritDoc} */
-    public InlineArea get(LayoutContext context) {
-        curArea = getPageNumberCitationInlineArea();
-        return curArea;
+    @Override
+    protected PageViewport getCitedPage() {
+        return getPSLM().getFirstPVWithID(fobj.getRefId());
     }
 
-    /**
-     * if id can be resolved then simply return a word, otherwise
-     * return a resolvable area
-     *
-     * TODO: [GA] May need to run bidi algorithm and script processor
-     * on resolved page number.
-     */
-    private InlineArea getPageNumberCitationInlineArea() {
-        PageViewport page = getPSLM().getFirstPVWithID(fobj.getRefId());
-        TextArea text = null;
-        int level = getBidiLevel();
-        if (page != null) {
-            String str = page.getPageNumberString();
-            // get page string from parent, build area
-            text = new TextArea();
-            int width = getStringWidth(str);    // TODO: [GA] !I18N!
-            text.setBidiLevel(level);
-            text.addWord(str, 0, level);
-            text.setIPD(width);                 // TODO: [GA] !I18N!
-            resolved = true;
-        } else {
-            text = new UnresolvedPageNumber(fobj.getRefId(), font);
-            String str = "MMM"; // reserve three spaces for page number
-            int width = getStringWidth(str);    // TODO: [GA] !I18N!
-            text.setBidiLevel(level);
-            text.setIPD(width);                 // TODO: [GA] !I18N!
-            resolved = false;
-        }
-        updateTextAreaTraits(text);
-        return text;
+    @Override
+    protected boolean getReferenceType() {
+        return UnresolvedPageNumber.FIRST;
     }
 
 }

src/java/org/apache/fop/layoutmgr/inline/PageNumberLayoutManager.java

@@ -85,14 +85,13 @@ public class PageNumberLayoutManager extends LeafNodeLayoutManager {
         text.setBaselineOffset(font.getAscender());
         TraitSetter.addFontTraits(text, font);
         text.addTrait(Trait.COLOR, fobj.getColor());
-        TraitSetter.addStructureTreeElement(text, fobj.getStructureTreeElement());
         TraitSetter.addTextDecoration(text, fobj.getTextDecoration());
 
         return text;
     }
 
     /** {@inheritDoc} */
-    protected InlineArea getEffectiveArea() {
+    protected InlineArea getEffectiveArea(LayoutContext layoutContext) {
         TextArea baseArea = (TextArea)curArea;
         //TODO Maybe replace that with a clone() call or better, a copy constructor
         //TODO or even better: delay area creation until addAreas() stage
@@ -105,6 +104,9 @@ public class PageNumberLayoutManager extends LeafNodeLayoutManager {
         ta.setBaselineOffset(baseArea.getBaselineOffset());
         ta.addTrait(Trait.COLOR, fobj.getColor()); //only to initialize the trait map
         ta.getTraits().putAll(baseArea.getTraits());
+        if (!layoutContext.treatAsArtifact()) {
+            TraitSetter.addStructureTreeElement(ta, fobj.getStructureTreeElement());
+        }
         updateContent(ta);
         return ta;
     }

src/java/org/apache/fop/layoutmgr/inline/TextLayoutManager.java

@@ -469,7 +469,9 @@ public class TextLayoutManager extends LeafNodeLayoutManager {
             TraitSetter.addFontTraits(textArea, font);
             textArea.addTrait(Trait.COLOR, foText.getColor());
             TraitSetter.addTextDecoration(textArea, foText.getTextDecoration());
-            TraitSetter.addStructureTreeElement(textArea, foText.getStructureTreeElement());
+            if (!context.treatAsArtifact()) {
+                TraitSetter.addStructureTreeElement(textArea, foText.getStructureTreeElement());
+            }
             return textArea;
         }
 

src/java/org/apache/fop/layoutmgr/inline/WrapperLayoutManager.java

@@ -71,7 +71,7 @@ public class WrapperLayoutManager extends LeafNodeLayoutManager {
                 TraitSetter.setProducerID(helperBlock, fobj.getId());
                 parentLayoutManager.addChildArea(helperBlock);
             } else {
-                InlineArea area = getEffectiveArea();
+                InlineArea area = getEffectiveArea(context);
                 parentLayoutManager.addChildArea(area);
             }
         }

src/java/org/apache/fop/layoutmgr/list/ListBlockLayoutManager.java

@@ -141,7 +141,7 @@ public class ListBlockLayoutManager extends BlockStackingLayoutManager
         // the list block contains areas stacked from each list item
 
         LayoutManager childLM;
-        LayoutContext lc = new LayoutContext(0);
+        LayoutContext lc = LayoutContext.offspringOf(layoutContext);
         LayoutManager firstLM = null;
         LayoutManager lastLM = null;
         Position firstPos = null;

src/java/org/apache/fop/layoutmgr/list/ListItemContentLayoutManager.java

@@ -101,7 +101,7 @@ public class ListItemContentLayoutManager extends BlockStackingLayoutManager imp
         addId();
 
         LayoutManager childLM;
-        LayoutContext lc = new LayoutContext(0);
+        LayoutContext lc = LayoutContext.offspringOf(layoutContext);
         LayoutManager firstLM = null;
         LayoutManager lastLM = null;
         Position firstPos = null;

src/java/org/apache/fop/layoutmgr/list/ListItemLayoutManager.java

@@ -488,7 +488,7 @@ public class ListItemLayoutManager extends BlockStackingLayoutManager implements
 
         addId();
 
-        LayoutContext lc = new LayoutContext(0);
+        LayoutContext lc = LayoutContext.offspringOf(layoutContext);
         Position firstPos = null;
         Position lastPos = null;
 

src/java/org/apache/fop/layoutmgr/table/RowGroupLayoutManager.java

@@ -112,7 +112,7 @@ class RowGroupLayoutManager {
                         spanWidth += ((TableColumn) colIter.next()).getColumnWidth().getValue(
                                 tableLM);
                     }
-                    LayoutContext childLC = new LayoutContext(0);
+                    LayoutContext childLC = LayoutContext.newInstance();
                     childLC.setStackLimitBP(context.getStackLimitBP()); //necessary?
                     childLC.setRefIPD(spanWidth);
 

src/java/org/apache/fop/layoutmgr/table/TableAndCaptionLayoutManager.java

@@ -81,7 +81,7 @@ public class TableAndCaptionLayoutManager extends BlockStackingLayoutManager {
             int ipd = context.getRefIPD();
             BreakPoss bp;
 
-            LayoutContext childLC = new LayoutContext(0);
+            LayoutContext childLC = LayoutContext.newInstance();
             // if line layout manager then set stack limit to ipd
             // line LM actually generates a LineArea which is a block
             childLC.setStackLimit(
@@ -145,7 +145,7 @@ public class TableAndCaptionLayoutManager extends BlockStackingLayoutManager {
         /* TODO: Reimplement using Knuth approach
         LayoutManager childLM;
         int iStartPos = 0;
-        LayoutContext lc = new LayoutContext(0);
+        LayoutContext lc = LayoutContext.newInstance();
         while (parentIter.hasNext()) {
             LeafPosition lfp = (LeafPosition) parentIter.next();
             // Add the block areas to Area

src/java/org/apache/fop/layoutmgr/table/TableCaptionLayoutManager.java

@@ -76,7 +76,7 @@ public class TableCaptionLayoutManager extends BlockStackingLayoutManager {
             int ipd = context.getRefIPD();
             BreakPoss bp;
 
-            LayoutContext childLC = new LayoutContext(0);
+            LayoutContext childLC = LayoutContext.newInstance();
             // if line layout manager then set stack limit to ipd
             // line LM actually generates a LineArea which is a block
             childLC.setStackLimit(
@@ -141,7 +141,7 @@ public class TableCaptionLayoutManager extends BlockStackingLayoutManager {
         /* TODO: Reimplement using Knuth approach
         LayoutManager childLM;
         int iStartPos = 0;
-        LayoutContext lc = new LayoutContext(0);
+        LayoutContext lc = LayoutContext.newInstance();
         while (parentIter.hasNext()) {
             LeafPosition lfp = (LeafPosition) parentIter.next();
             // Add the block areas to Area

src/java/org/apache/fop/layoutmgr/table/TableCellLayoutManager.java

@@ -144,7 +144,7 @@ public class TableCellLayoutManager extends BlockStackingLayoutManager
         LayoutManager curLM; // currently active LM
         LayoutManager prevLM = null; // previously active LM
         while ((curLM = getChildLM()) != null) {
-            LayoutContext childLC = new LayoutContext(0);
+            LayoutContext childLC = LayoutContext.newInstance();
             // curLM is a ?
             childLC.setStackLimitBP(context.getStackLimitBP().minus(stackLimit));
             childLC.setRefIPD(cellIPD);

src/java/org/apache/fop/layoutmgr/table/TableContentLayoutManager.java

@@ -71,6 +71,8 @@ public class TableContentLayoutManager implements PercentBaseContext {
 
     private TableStepper stepper;
 
+    private boolean headerIsBeingRepeated;
+
     /**
      * Main constructor
      * @param parent Parent layout manager
@@ -383,6 +385,7 @@ public class TableContentLayoutManager implements PercentBaseContext {
                 }
             }
         }
+        boolean treatFooterAsArtifact = layoutContext.treatAsArtifact();
         if (lastPos instanceof TableHFPenaltyPosition) {
             TableHFPenaltyPosition penaltyPos = (TableHFPenaltyPosition)lastPos;
             LOG.debug("Break at penalty!");
@@ -393,6 +396,7 @@ public class TableContentLayoutManager implements PercentBaseContext {
             }
             if (penaltyPos.footerElements != null) {
                 footerElements = penaltyPos.footerElements;
+                treatFooterAsArtifact = true;
             }
         }
 
@@ -403,10 +407,18 @@ public class TableContentLayoutManager implements PercentBaseContext {
         }
 
         if (headerElements != null) {
+            boolean ancestorTreatAsArtifact = layoutContext.treatAsArtifact();
+            if (headerIsBeingRepeated) {
+                layoutContext.setTreatAsArtifact(true);
+            }
             //header positions for the last part are the second-to-last element and need to
             //be handled first before all other TableContentPositions
             addHeaderFooterAreas(headerElements, tableLM.getTable().getTableHeader(), painter,
                     false);
+            if (!ancestorTreatAsArtifact) {
+                headerIsBeingRepeated = true;
+            }
+            layoutContext.setTreatAsArtifact(ancestorTreatAsArtifact);
         }
 
         if (tablePositions.isEmpty()) {
@@ -419,9 +431,12 @@ public class TableContentLayoutManager implements PercentBaseContext {
         }
 
         if (footerElements != null) {
+            boolean ancestorTreatAsArtifact = layoutContext.treatAsArtifact();
+            layoutContext.setTreatAsArtifact(treatFooterAsArtifact);
             //Positions for footers are simply added at the end
             addHeaderFooterAreas(footerElements, tableLM.getTable().getTableFooter(), painter,
                     true);
+            layoutContext.setTreatAsArtifact(ancestorTreatAsArtifact);
         }
 
         this.usedBPD += painter.getAccumulatedBPD();

src/java/org/apache/fop/layoutmgr/table/TableLayoutManager.java

@@ -242,7 +242,7 @@ public class TableLayoutManager extends BlockStackingLayoutManager
         // Elements for the table-header/footer/body
         List contentKnuthElements;
         contentLM = new TableContentLayoutManager(this);
-        LayoutContext childLC = new LayoutContext(0);
+        LayoutContext childLC = LayoutContext.newInstance();
         /*
         childLC.setStackLimit(
               MinOptMax.subtract(context.getStackLimit(),
@@ -355,7 +355,7 @@ public class TableLayoutManager extends BlockStackingLayoutManager
         // BPD of the table, i.e., height of its content; table's borders and paddings not counted
         int tableHeight = 0;
         //Body childLM;
-        LayoutContext lc = new LayoutContext(0);
+        LayoutContext lc = LayoutContext.offspringOf(layoutContext);
 
 
         lc.setRefIPD(getContentAreaIPD());

src/java/org/apache/fop/pdf/PDFStructElem.java

@@ -72,9 +72,7 @@ public class PDFStructElem extends PDFDictionary implements StructureTreeElement
     }
 
     /**
-     * Add a kid to 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.
+     * Adds a kid to this structure element.
      *
      * @param kid element to be added
      */

status.xml

@@ -63,6 +63,12 @@
       documents. Example: the fix of marks layering will be such a case when it's done.
     -->
     <release version="FOP Trunk" date="TBD">
+      <action context="Renderers" dev="VH" type="add" importance="high">
+        When PDF accessibility is enabled, treat repeated table headings as artifacts. This allows 
+        screen readers to read the header only once at the beginning of the table and the footer 
+        once at the end of a table. Reading the headings at every column or page break is likely to 
+        disturb the user. This follows Section 508 recommendations.
+      </action>
       <action context="Layout" dev="VH" type="fix">
         An IllegalArgumentException was thrown when break-before was used inside a list.
       </action>