feature/185-parser-serializer-roundtrip-xml

src/main/java/fr/inria/corese/core/next/impl/io/parser/rdfxml/RDFXMLParser.java

@@ -174,7 +174,6 @@ private void handleEndElement(String uri, String localName, String qName) {
             IRI predicate = ctx.predicateStack.pop();
             Resource subject = ctx.subjectStack.peek();
             String datatypeUri = ctx.datatypeStack.isEmpty() ? null : ctx.datatypeStack.pop();
-            //emitLiteral(subject, predicate, text, datatypeUri);
             String lang = ctx.langStack.isEmpty() ? null : ctx.langStack.peek();
             emitter.emitLiteral(subject, predicate, text, datatypeUri, lang);
             return;
@@ -213,7 +212,8 @@ private void updateLang(Attributes attrs) {
     private void updateDatatype(Attributes attrs) {
         String datatype = attrs.getValue(RDF.type.getNamespace(), "datatype");
         if (datatype != null) {
-            ctx.datatypeStack.push(datatype);
+            String expanded = expandQNameFromQName(datatype);
+            ctx.datatypeStack.push(expanded);
         }
     }
 

src/main/java/fr/inria/corese/core/next/impl/io/parser/rdfxml/RDFXMLUtils.java

@@ -48,6 +48,21 @@ public static Optional<XSD> resolveDatatype(String datatypeUri) {
         return Optional.empty();
     }
 
+    /**
+     * Expands a QName string (e.g. "xsd:integer") into a full URI if known.
+     * Currently supports "xsd:" → XML Schema namespace.
+     *
+     * @param qname the QName string
+     * @return expanded full URI if a known prefix, otherwise returns qname unchanged
+     */
+    public static String expandQNameFromQName(String qname) {
+        if (qname == null) return null;
+        if (qname.startsWith("xsd:")) {
+            return "http://www.w3.org/2001/XMLSchema#" + qname.substring("xsd:".length());
+        }
+        return qname;
+    }
+
     /**
      * Extracts a subject resource from RDF/XML attributes.
      * Supports rdf:about, rdf:nodeID, rdf:ID.

src/main/java/fr/inria/corese/core/next/impl/io/parser/turtle/TurtleListenerImpl.java

@@ -117,11 +117,17 @@ private String resolveIRI(String raw) {
      * @return the stripped string
      */
     private String stripQuotes(String text) {
-        if (text == null || text.length() < 2)
+        if (text == null || text.length() < 2) {
             return text;
+        }
+        if (text.startsWith("\"\"\"") && text.endsWith("\"\"\"") && text.length() >= 6) {
+            return text.substring(3, text.length() - 3);
+        }
+        if (text.startsWith("'''") && text.endsWith("'''") && text.length() >= 6) {
+            return text.substring(3, text.length() - 3);
+        }
         if ((text.startsWith("\"") && text.endsWith("\"")) ||
-                (text.startsWith("'''") && text.endsWith("'''")) ||
-                (text.startsWith("\"\"\"") && text.endsWith("\"\"\""))) {
+                (text.startsWith("'") && text.endsWith("'"))) {
             return text.substring(1, text.length() - 1);
         }
         return text;

src/main/java/fr/inria/corese/core/next/impl/io/serialization/base/AbstractGraphSerializer.java

@@ -322,18 +322,23 @@ protected void writeValue(Writer writer, Value value) throws IOException {
             currentlyWritingBlankNodes.add(bNode);
 
             boolean handled = false;
-            if (option instanceof AbstractSerializerOption && getTFamilyOption().useCollections() && bNode.isBNode()) {
-                handled = writeRDFList(writer, bNode);
-            }
 
-            if (!handled && option instanceof AbstractSerializerOption && getTFamilyOption().getBlankNodeStyle() == BlankNodeStyleEnum.ANONYMOUS && bNode.isBNode()) { // getBlankNodeStyle is on AbstractTFamilyConfig
-                List<Statement> properties = model.stream()
-                        .filter(stmt -> stmt.getSubject().equals(bNode))
-                        .toList();
+            boolean isSubject = model.stream().anyMatch(stmt -> stmt.getSubject().equals(bNode));
+
+            if (!isSubject && option instanceof AbstractSerializerOption) {
+                if (getTFamilyOption().useCollections() && bNode.isBNode()) {
+                    handled = writeRDFList(writer, bNode);
+                }
+
+                if (!handled && getTFamilyOption().getBlankNodeStyle() == BlankNodeStyleEnum.ANONYMOUS && bNode.isBNode()) {
+                    List<Statement> properties = model.stream()
+                            .filter(stmt -> stmt.getSubject().equals(bNode))
+                            .toList();
 
-                if (!properties.isEmpty()) {
-                    writeInlineBlankNode(writer, properties);
-                    handled = true;
+                    if (!properties.isEmpty()) {
+                        writeInlineBlankNode(writer, properties);
+                        handled = true;
+                    }
                 }
             }
 
@@ -343,10 +348,12 @@ protected void writeValue(Writer writer, Value value) throws IOException {
 
             currentlyWritingBlankNodes.remove(bNode);
         } else {
-            throw new IllegalArgumentException("Unsupported value type for " + getFormatName() + " serialization: " + value.getClass().getName());
+            throw new IllegalArgumentException("Unsupported value type for " + getFormatName() +
+                    " serialization: " + value.getClass().getName());
         }
     }
 
+
     /**
      * Writes an {@link IRI} to the writer.
      * Attempts to use a prefixed name if possible, otherwise writes the full IRI in angle brackets.
@@ -661,48 +668,8 @@ protected Set<Resource> precomputeInlineBlankNodesAndLists() {
             if (stmt.getSubject().isBNode()) {
                 Resource bNodeSubject = stmt.getSubject();
                 if (tFamilyConfig.useCollections() && isRDFListHead(bNodeSubject)) {
-                    Resource current = bNodeSubject;
-                    Set<Resource> listNodes = new HashSet<>();
-                    Set<Resource> visitedInPrecomp = new HashSet<>();
-                    boolean isList = true;
-                    while (current != null && current.isBNode() && !visitedInPrecomp.contains(current)) {
-                        visitedInPrecomp.add(current);
-                        listNodes.add(current);
-                        final Resource finalCurrentForLambda = current;
-                        List<Statement> listProps = model.stream()
-                                .filter(s -> s.getSubject().equals(finalCurrentForLambda))
-                                .toList();
-
-                        if (listProps.size() != 2) {
-                            isList = false;
-                            break;
-                        }
-
-                        Optional<Value> first = listProps.stream()
-                                .filter(s -> s.getPredicate().stringValue().equals(SerializationConstants.RDF_FIRST))
-                                .map(Statement::getObject)
-                                .findFirst();
-
-                        Optional<Value> rest = listProps.stream()
-                                .filter(s -> s.getPredicate().stringValue().equals(SerializationConstants.RDF_REST))
-                                .map(Statement::getObject)
-                                .findFirst();
-
-                        if (!first.isPresent() || !rest.isPresent()) {
-                            isList = false;
-                            break;
-                        }
-
-                        if (rest.get().stringValue().equals(SerializationConstants.RDF_NIL)) {
-                            current = null;
-                        } else if (rest.get().isBNode()) {
-                            current = (Resource) rest.get();
-                        } else {
-                            isList = false;
-                            break;
-                        }
-                    }
-                    if (isList && current == null) {
+                    Set<Resource> listNodes = detectListNodes(bNodeSubject);
+                    if (!listNodes.isEmpty()) {
                         precomputed.addAll(listNodes);
                     }
                 }
@@ -716,7 +683,10 @@ protected Set<Resource> precomputeInlineBlankNodesAndLists() {
                                     s.getPredicate().stringValue().equals(SerializationConstants.RDF_REST)
                     );
 
-                    if (!properties.isEmpty() && !isPartOfList) {
+                    boolean usedAsTopLevelSubject = model.stream()
+                            .anyMatch(s -> s.getSubject().equals(bNodeSubject));
+
+                    if (!properties.isEmpty() && !isPartOfList && !usedAsTopLevelSubject) {
                         precomputed.add(bNodeSubject);
                     }
                 }
@@ -725,6 +695,55 @@ protected Set<Resource> precomputeInlineBlankNodesAndLists() {
         return precomputed;
     }
 
+    /**
+     * Traverses an RDF list starting from the given head and collects all list nodes.
+     *
+     * @param head the blank node that may be the head of an RDF list
+     * @return the set of blank nodes that form the list, or an empty set if not a valid list
+     */
+    private Set<Resource> detectListNodes(Resource head) {
+        Set<Resource> listNodes = new HashSet<>();
+        Set<Resource> visited = new HashSet<>();
+        Resource current = head;
+
+        while (current != null && current.isBNode() && !visited.contains(current)) {
+            visited.add(current);
+            listNodes.add(current);
+
+            final Resource finalCurrent = current;
+            List<Statement> props = model.stream()
+                    .filter(s -> s.getSubject().equals(finalCurrent))
+                    .toList();
+
+            if (props.size() != 2) {
+                return Collections.emptySet();
+            }
+
+            Optional<Value> first = props.stream()
+                    .filter(s -> s.getPredicate().stringValue().equals(SerializationConstants.RDF_FIRST))
+                    .map(Statement::getObject)
+                    .findFirst();
+
+            Optional<Value> rest = props.stream()
+                    .filter(s -> s.getPredicate().stringValue().equals(SerializationConstants.RDF_REST))
+                    .map(Statement::getObject)
+                    .findFirst();
+
+            if (!first.isPresent() || !rest.isPresent()) {
+                return Collections.emptySet();
+            }
+
+            if (rest.get().stringValue().equals(SerializationConstants.RDF_NIL)) {
+                current = null;
+            } else if (rest.get().isBNode()) {
+                current = (Resource) rest.get();
+            } else {
+                return Collections.emptySet();
+            }
+        }
+        return current == null ? listNodes : Collections.emptySet();
+    }
+
     /**
      * Checks if a given blank node is the head of an RDF list.
      *

src/main/java/fr/inria/corese/core/next/impl/io/serialization/jsonld/TitaniumRDFDatasetSerializationAdapter.java

@@ -38,13 +38,16 @@
 import fr.inria.corese.core.next.impl.common.vocabulary.RDF;
 import fr.inria.corese.core.next.impl.common.vocabulary.XSD;
 import fr.inria.corese.core.next.impl.exception.SerializationException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * Adapter class from Model to RdfDataset for usage in the JSON-LD serialization process using the titanium library.
  * @see <a href="https://github.com/filip26/titanium-rdf-api">Titanium RDF API</a>
  */
 public class TitaniumRDFDatasetSerializationAdapter implements RdfDataset {
 
+    private final static Logger logger = LoggerFactory.getLogger(TitaniumRDFDatasetSerializationAdapter.class);
     private Model model;
 
     /**
@@ -58,17 +61,18 @@ public TitaniumRDFDatasetSerializationAdapter(Model model) {
 
     @Override
     public RdfGraph getDefaultGraph() {
-        return new RdfGraph() {
+        RdfGraph resultGraph = new RdfGraph() {
             @Override
             public boolean contains(RdfTriple triple) {
-                return model.contains(toResource(triple.getSubject()), toIRI(triple.getPredicate()), toValue(triple.getObject()));
+                return model.contains(toResource(triple.getSubject()), toIRI(triple.getPredicate()), toValue(triple.getObject()), (Resource) null);
             }
 
             @Override
             public List<RdfTriple> toList() {
-                return model.stream().map(TitaniumRDFDatasetSerializationAdapter.this::toRdfTriple).toList();
+                return model.filter(null, null, null, (Resource) null).stream().map(TitaniumRDFDatasetSerializationAdapter.this::toRdfTriple).toList();
             }
         };
+        return resultGraph;
     }
 
     @Override
@@ -187,27 +191,15 @@ public RdfValue getObject() {
      * @return the converted resource
      */
     private RdfResource toRdfResource(Resource resource) {
-        if (resource != null && (! (resource.isBNode() || resource.isIRI()))) {
-            throw new SerializationException("Unknown resource type " + resource, "JSON-LD");
-        } else if (resource == null) {
+        if (resource == null) {
             return null;
+        } else if (resource.isIRI()) {
+            return toRdfIRI((IRI) resource);
+        } else if (resource.isBNode()) {
+            return toRdfBlankNode((BNode) resource);
+        } else {
+            throw new SerializationException("Unknown resource type " + resource, "JSON-LD");
         }
-        return new RdfResource() {
-            @Override
-            public boolean isIRI() {
-                return resource.isIRI();
-            }
-
-            @Override
-            public boolean isBlankNode() {
-                return resource.isBNode();
-            }
-
-            @Override
-            public String getValue() {
-                return resource.stringValue();
-            }
-        };
     }
 
     /**
@@ -258,7 +250,7 @@ public boolean isBlankNode() {
             }
             @Override
             public String getValue() {
-                return bnode.stringValue();
+                return "_:" + bnode.stringValue();
             }
         };
     }
@@ -290,7 +282,7 @@ public String getDatatype() {
                     ) {
                     return literal.getDatatype().stringValue();
                 } else if (literal.getLanguage().isPresent()) {
-                    return RDF.langString.getIRI().stringValue();
+                    return "rdf:langString"; // Titanium JSONLD expect the langstring datatype to be in this format ...
                 } else {
                     return XSD.xsdString.getIRI().stringValue();
                 }

src/main/java/fr/inria/corese/core/next/impl/io/serialization/turtle/TurtleSerializer.java

@@ -143,16 +143,20 @@ protected String escapeLiteralString(String value) {
                 case '"':
                     sb.append(SerializationConstants.BACK_SLASH).append(SerializationConstants.QUOTE);
                     break;
-                case '\\':
-                    sb.append(SerializationConstants.BACK_SLASH).append(SerializationConstants.BACK_SLASH);
-                    break;
                 default:
-                    if (option.escapeUnicode() && (c <= 0x1F || c == 0x7F || (c >= 0x80 && c <= 0xFFFF))) {
+                    if (Character.isISOControl(c) ||c == 0x7F) {
+                        sb.append(String.format("\\u%04X", (int) c));
+                }
+                    else if (option.escapeUnicode() && c >= 0x80 && c <= 0xFFFF) {
                         sb.append(String.format("\\u%04X", (int) c));
                     } else if (Character.isHighSurrogate(c)) {
                         int codePoint = value.codePointAt(i);
                         if (Character.isValidCodePoint(codePoint)) {
-                            sb.append(String.format("\\U%08X", codePoint));
+                            if (option.escapeUnicode()) {
+                                sb.append(String.format("\\U%08X", codePoint));
+                            } else {
+                                sb.append(Character.toChars(codePoint));
+                            }
                             i++;
                         } else {
                             sb.append(c);
@@ -178,6 +182,7 @@ protected String escapeMultilineLiteralString(String value) {
                 SerializationConstants.BACK_SLASH + SerializationConstants.QUOTE +
                         SerializationConstants.BACK_SLASH + SerializationConstants.QUOTE +
                         SerializationConstants.BACK_SLASH + SerializationConstants.QUOTE);
+
     }
 
     /**

src/test/java/fr/inria/corese/core/next/impl/io/parser/jsonld/JSONLDCircularTest.java

@@ -27,6 +27,8 @@
 import fr.inria.corese.core.next.impl.io.serialization.DefaultSerializerFactory;
 import fr.inria.corese.core.next.impl.temp.CoreseAdaptedValueFactory;
 import fr.inria.corese.core.next.impl.temp.CoreseModel;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 /**
  * Circular tests for JSON-LD parser and serializer integration.
@@ -42,6 +44,8 @@
 @DisplayName("JSON-LD Circular Integration Tests")
 class JSONLDCircularTest {
 
+    private static final Logger logger = LoggerFactory.getLogger(JSONLDCircularTest.class);
+
     private ValueFactory valueFactory;
     private SerializerFactory serializerFactory;
     private ParserFactory parserFactory;
@@ -69,7 +73,8 @@ void setUp() {
         valueFactory = new CoreseAdaptedValueFactory();
         serializerFactory = new DefaultSerializerFactory();
         parserFactory = new ParserFactory();
-        defaultConfig = new TitaniumJSONLDProcessorOption.Builder().build();
+        defaultConfig = new TitaniumJSONLDProcessorOption.Builder()
+                .build();
     }
 
     /**
@@ -261,7 +266,7 @@ private Model createSpecialCharactersTestModel() {
     private Model performRoundTrip(Model originalModel) throws Exception {
         // Serialize to JSON-LD
         RDFSerializer serializer = serializerFactory.createSerializer(
-                RDFFormat.JSONLD, originalModel, (SerializationOption) defaultConfig);
+                RDFFormat.JSONLD, originalModel, defaultConfig);
 
         StringWriter writer = new StringWriter();
         serializer.write(writer);