Added possibility to treat some content as artifact.

If any fo:static-content or fo:wrapper element has their 'role' property set to 'artifact', then they and their descendants will be treated as artifacts.

Suggested by Martin Koegler as part of Bugzilla #50852


git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@1343632 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/fop/accessibility/Accessibility.java

@@ -28,6 +28,12 @@ public final class Accessibility {
     /** Constant string for the rendering options key to enable accessibility features. */
     public static final String ACCESSIBILITY = "accessibility";
 
+    /**
+     * The value to be set on the 'role' property for the element and its descendants to
+     * be considered as artifacts.
+     */
+    public static final String ROLE_ARTIFACT = "artifact";
+
     private Accessibility() { }
 
 }

src/java/org/apache/fop/accessibility/fo/FO2StructureTreeConverter.java

@@ -23,6 +23,7 @@ import java.util.Stack;
 
 import org.xml.sax.SAXException;
 
+import org.apache.fop.accessibility.Accessibility;
 import org.apache.fop.accessibility.StructureTreeEventHandler;
 import org.apache.fop.fo.DelegatingFOEventHandler;
 import org.apache.fop.fo.FOEventHandler;
@@ -57,6 +58,8 @@ import org.apache.fop.fo.pagination.Flow;
 import org.apache.fop.fo.pagination.PageSequence;
 import org.apache.fop.fo.pagination.Root;
 import org.apache.fop.fo.pagination.StaticContent;
+import org.apache.fop.fo.properties.CommonAccessibility;
+import org.apache.fop.fo.properties.CommonAccessibilityHolder;
 
 /**
  * Allows to create the structure tree of an FO document, by converting FO
@@ -355,6 +358,7 @@ public class FO2StructureTreeConverter extends DelegatingFOEventHandler {
 
     @Override
     public void startStatic(StaticContent staticContent) {
+        handleStartArtifact(staticContent);
         converter.startStatic(staticContent);
         super.startStatic(staticContent);
     }
@@ -362,6 +366,7 @@ public class FO2StructureTreeConverter extends DelegatingFOEventHandler {
     @Override
     public void endStatic(StaticContent statisContent) {
         converter.endStatic(statisContent);
+        handleEndArtifact(statisContent);
         super.endStatic(statisContent);
     }
 
@@ -454,6 +459,7 @@ public class FO2StructureTreeConverter extends DelegatingFOEventHandler {
 
     @Override
     public void startWrapper(Wrapper wrapper) {
+        handleStartArtifact(wrapper);
         converter.startWrapper(wrapper);
         super.startWrapper(wrapper);
     }
@@ -461,6 +467,7 @@ public class FO2StructureTreeConverter extends DelegatingFOEventHandler {
     @Override
     public void endWrapper(Wrapper wrapper) {
         converter.endWrapper(wrapper);
+        handleEndArtifact(wrapper);
         super.endWrapper(wrapper);
     }
 
@@ -488,4 +495,22 @@ public class FO2StructureTreeConverter extends DelegatingFOEventHandler {
         super.endExternalDocument(document);
     }
 
+    private void handleStartArtifact(CommonAccessibilityHolder fobj) {
+        if (isArtifact(fobj)) {
+            converters.push(converter);
+            converter = eventSwallower;
+        }
+    }
+
+    private void handleEndArtifact(CommonAccessibilityHolder fobj) {
+        if (isArtifact(fobj)) {
+            converter = converters.pop();
+        }
+    }
+
+    private boolean isArtifact(CommonAccessibilityHolder fobj) {
+        CommonAccessibility accessibility = fobj.getCommonAccessibility();
+        return Accessibility.ROLE_ARTIFACT.equalsIgnoreCase(accessibility.getRole());
+    }
+
 }

src/java/org/apache/fop/fo/flow/Wrapper.java

@@ -26,7 +26,10 @@ import org.apache.fop.fo.Constants;
 import org.apache.fop.fo.FONode;
 import org.apache.fop.fo.FOText;
 import org.apache.fop.fo.FObjMixed;
+import org.apache.fop.fo.PropertyList;
 import org.apache.fop.fo.ValidationException;
+import org.apache.fop.fo.properties.CommonAccessibility;
+import org.apache.fop.fo.properties.CommonAccessibilityHolder;
 
 /**
  * Class modelling the <a href=http://www.w3.org/TR/xsl/#fo_wrapper">
@@ -34,13 +37,13 @@ import org.apache.fop.fo.ValidationException;
  * The <code>fo:wrapper</code> object serves as a property holder for
  * its child node objects.
  */
-public class Wrapper extends FObjMixed {
-    // The value of properties relevant for fo:wrapper.
-    // End of property values
+public class Wrapper extends FObjMixed implements CommonAccessibilityHolder {
 
     // used for FO validation
     private boolean blockOrInlineItemFound = false;
 
+    private CommonAccessibility commonAccessibility;
+
     /**
      * Create a Wrapper instance that is a child of the
      * given {@link FONode}
@@ -51,6 +54,12 @@ public class Wrapper extends FObjMixed {
         super(parent);
     }
 
+    @Override
+    public void bind(PropertyList pList) throws FOPException {
+        super.bind(pList);
+        commonAccessibility = CommonAccessibility.getInstance(pList);
+    }
+
     @Override
     protected void startOfNode() throws FOPException {
         super.startOfNode();
@@ -136,6 +145,10 @@ public class Wrapper extends FObjMixed {
         return FO_WRAPPER;
     }
 
+    public CommonAccessibility getCommonAccessibility() {
+        return commonAccessibility;
+    }
+
     @Override
     public boolean isDelimitedTextRangeBoundary ( int boundary ) {
         return false;

test/java/org/apache/fop/accessibility/fo/FO2StructureTreeConverterTestCase.java

@@ -19,8 +19,6 @@
 
 package org.apache.fop.accessibility.fo;
 
-import static org.junit.Assert.assertTrue;
-
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
@@ -45,6 +43,8 @@ import org.w3c.dom.Document;
 import org.xml.sax.SAXException;
 import org.xml.sax.helpers.AttributesImpl;
 
+import static org.junit.Assert.assertTrue;
+
 import org.apache.fop.accessibility.StructureTree2SAXEventAdapter;
 import org.apache.fop.accessibility.StructureTreeEventHandler;
 import org.apache.fop.apps.FOPException;
@@ -102,6 +102,17 @@ public class FO2StructureTreeConverterTestCase {
         testConverter();
     }
 
+    @Test
+    public void testArtifact() throws Exception {
+        foLoader = new FOLoader() {
+
+            public InputStream getFoInputStream() {
+                return getResource("artifact.fo");
+            }
+        };
+        testConverter();
+    }
+
     private Transformer createTransformer(Source xslt) throws TransformerFactoryConfigurationError,
             TransformerConfigurationException {
         TransformerFactory transformerFactory = TransformerFactory.newInstance();

test/java/org/apache/fop/accessibility/fo/artifact.fo

@@ -0,0 +1,97 @@
+<?xml version="1.0" standalone="no"?>
+<fo:root xmlns:fo="http://www.w3.org/1999/XSL/Format">
+  <fo:layout-master-set>
+    <fo:simple-page-master master-name="page"
+      page-height="500pt" page-width="300pt" margin="20pt">
+      <fo:region-body/>
+    </fo:simple-page-master>
+  </fo:layout-master-set>
+
+  <fo:page-sequence master-reference="page">
+    <fo:flow flow-name="xsl-region-body" text-align="justify">
+
+      <fo:block>This piece of text is normal content that should be read out loud by a screen 
+        reader.</fo:block>
+
+      <fo:block space-before="10pt">The following content will be treated as artifact:</fo:block>
+
+      <fo:wrapper role="artifact">
+        <fo:block-container border="1pt solid black" padding="5pt"  background-color="#F0F0F0" 
+          space-before="10pt" start-indent="6pt" end-indent="6pt" color="#606060">
+          <fo:block start-indent="0" end-indent="0">
+            <fo:block>A block as artifact.</fo:block>
+            <fo:table space-before="5pt" width="100%" table-layout="fixed">
+              <fo:table-column column-width="proportional-column-width(1)"/>
+              <fo:table-column column-width="proportional-column-width(2)"/>
+              <fo:table-header>
+                <fo:table-cell border="1pt solid #606060"><fo:block>Header 1.1</fo:block></fo:table-cell>
+                <fo:table-cell border="1pt solid #606060"><fo:block>Header 1.2</fo:block></fo:table-cell>
+              </fo:table-header>
+              <fo:table-footer>
+                <fo:table-cell border="1pt solid #606060"><fo:block>Footer 1.1</fo:block></fo:table-cell>
+                <fo:table-cell border="1pt solid #606060"><fo:block>Footer 1.2</fo:block></fo:table-cell>
+              </fo:table-footer>
+              <fo:table-body>
+                <fo:table-row>
+                  <fo:table-cell border="1pt solid #606060"><fo:block>Cell 1.1</fo:block></fo:table-cell>
+                  <fo:table-cell border="1pt solid #606060"><fo:block>Cell 1.2</fo:block></fo:table-cell>
+                </fo:table-row>
+                <fo:table-row>
+                  <fo:table-cell border="1pt solid #606060"><fo:block>Cell 2.1</fo:block></fo:table-cell>
+                  <fo:table-cell border="1pt solid #606060"><fo:block>Cell 2.2</fo:block></fo:table-cell>
+                </fo:table-row>
+              </fo:table-body>
+            </fo:table>
+            <fo:list-block space-before="7pt" provisional-distance-between-starts="8pt" 
+              provisional-label-separation="5pt">
+              <fo:list-item>
+                <fo:list-item-label end-indent="label-end()">
+                  <fo:block>•</fo:block>
+                </fo:list-item-label>
+                <fo:list-item-body start-indent="body-start()">
+                  <fo:block>Item 1.</fo:block>
+                </fo:list-item-body>
+              </fo:list-item>
+              <fo:list-item>
+                <fo:list-item-label end-indent="label-end()">
+                  <fo:block>•</fo:block>
+                </fo:list-item-label>
+                <fo:list-item-body start-indent="body-start()">
+                  <fo:block>Item 2.</fo:block>
+                </fo:list-item-body>
+              </fo:list-item>
+              <fo:list-item>
+                <fo:list-item-label end-indent="label-end()">
+                  <fo:block>•</fo:block>
+                </fo:list-item-label>
+                <fo:list-item-body start-indent="body-start()">
+                  <fo:block>Item 3.</fo:block>
+                </fo:list-item-body>
+              </fo:list-item>
+            </fo:list-block>
+            <fo:wrapper>
+              <fo:block>A block in a nested wrapper.</fo:block>
+            </fo:wrapper>
+            <fo:wrapper role="artifact">
+              <fo:block>A block in a nested artifact wrapper.</fo:block>
+            </fo:wrapper>
+            <fo:wrapper>
+              <fo:block>Inside a nested wrapper.
+                <fo:wrapper role="artifact">An artifact wrapper inside the nested wrapper.
+                  <fo:inline><fo:wrapper>Inside a wrapper inside the artifact wrapper that is inside 
+                      the nested wrapper.</fo:wrapper> Outside the wrapper inside the artifact 
+                    wrapper that is inside the nested wrapper.</fo:inline>
+              </fo:wrapper> Outside the artifact wrapper.</fo:block>
+            </fo:wrapper>
+          </fo:block>
+        </fo:block-container>
+      </fo:wrapper>
+
+      <fo:block space-before="10pt">Now we are back to normal content that is part of the logical 
+        structure, should appear in the structure tree and should be read out loud by the screen 
+        reader.</fo:block>
+
+    </fo:flow>
+  </fo:page-sequence>
+
+</fo:root>

test/java/org/apache/fop/accessibility/fo/fo2StructureTree.xsl

@@ -105,6 +105,8 @@
     <xsl:call-template name="copy"/>
   </xsl:template>
 
+  <xsl:template match="fo:wrapper[translate(normalize-space(@role), 'ARTIFCT', 'artifct') = 'artifact']"/>
+
 
   <!-- Discard descendants of fo:leader -->
   <xsl:template match="fo:leader"/>

test/pdf/accessibility/role.fo

@@ -24,8 +24,8 @@
       <fo:region-after extent="10pt"/>
     </fo:simple-page-master>
   </fo:layout-master-set>
-  <fo:page-sequence master-reference="page" role="Art">
-    <fo:static-content flow-name="xsl-region-after" role="NonStruct" font-size="8pt">
+  <fo:page-sequence master-reference="page" language="en" country="GB" role="Art">
+    <fo:static-content flow-name="xsl-region-after" role="artifact" font-size="8pt">
       <fo:block text-align="center"><fo:page-number/></fo:block>
     </fo:static-content>
     <fo:flow flow-name="xsl-region-body" role="NonStruct"  hyphenate="true"