Jena 6 ont-api

pom.xml

@@ -141,6 +141,12 @@
                 </exclusion>
             </exclusions>
         </dependency>
+        <dependency>
+            <!-- new Jena ontology API (org.apache.jena.ontapi), replaces the deprecated-for-removal org.apache.jena.ontology -->
+            <groupId>org.apache.jena</groupId>
+            <artifactId>jena-ontapi</artifactId>
+            <version>6.1.0</version>
+        </dependency>
         <dependency>
             <groupId>org.slf4j</groupId>
             <artifactId>jcl-over-slf4j</artifactId>

src/main/java/com/atomgraph/core/Application.java

@@ -33,11 +33,8 @@
 import com.atomgraph.core.riot.RDFLanguages;
 import com.atomgraph.core.riot.lang.RDFPostReaderFactory;
 import com.atomgraph.core.server.Dispatcher;
-import com.atomgraph.core.util.jena.DataManager;
-import com.atomgraph.core.util.jena.DataManagerImpl;
 import com.atomgraph.core.vocabulary.A;
 import com.atomgraph.core.vocabulary.SD;
-import java.util.HashMap;
 import jakarta.annotation.PostConstruct;
 import jakarta.servlet.ServletConfig;
 import jakarta.ws.rs.client.Client;
@@ -48,7 +45,6 @@
 import org.apache.jena.riot.Lang;
 import org.apache.jena.riot.RDFDataMgr;
 import org.apache.jena.riot.resultset.ResultSetLang;
-import org.apache.jena.util.LocationMapper;
 import org.glassfish.hk2.utilities.binding.AbstractBinder;
 import org.glassfish.jersey.client.ClientConfig;
 import org.glassfish.jersey.server.ResourceConfig;
@@ -73,7 +69,6 @@ public class Application extends ResourceConfig implements com.atomgraph.core.mo
     private final Service service;
     private final MediaTypes mediaTypes;
     private final Client client;
-    private final DataManager dataManager;
     private final Integer maxGetRequestSize;
     private final boolean preemptiveAuth;
 
@@ -143,9 +138,6 @@ public Application(final Dataset dataset,
                     ResourceFactory.createResource(endpointURI), ResourceFactory.createResource(graphStoreURI), ResourceFactory.createResource(quadStoreURI),
                     authUser, authPwd, maxGetRequestSize);
         }
-
-        dataManager = new DataManagerImpl(LocationMapper.get(), new HashMap<>(), GraphStoreClient.create(client, mediaTypes),
-                cacheModelLoads, preemptiveAuth);
     }
 
     @PostConstruct
@@ -207,10 +199,6 @@ public Integer getMaxGetRequestSize()
         return maxGetRequestSize;
     }    
 
-    public DataManager getDataManager()
-    {
-        return dataManager;
-    }
 
     public boolean isPreemptiveAuth()
     {

src/main/java/com/atomgraph/core/io/DatasetProvider.java

@@ -32,8 +32,10 @@
 import org.apache.jena.rdf.model.Model;
 import org.apache.jena.riot.Lang;
 import org.apache.jena.riot.RDFDataMgr;
+import org.apache.jena.riot.RDFFormat;
 import org.apache.jena.riot.RDFLanguages;
 import org.apache.jena.riot.RDFParserRegistry;
+import org.apache.jena.riot.RDFWriter;
 import org.apache.jena.riot.RDFWriterRegistry;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -112,7 +114,14 @@ public void writeTo(Dataset dataset, Class<?> type, Type genericType, Annotation
         Lang lang = RDFLanguages.contentTypeToLang(formatType.toString()); // cannot be null - isWritable() checks that
 
         // if we need to provide triples, then we write only the default graph of the dataset
-        if (RDFLanguages.isTriples(lang)) dataset.getDefaultModel().write(entityStream, lang.getName());
+        if (RDFLanguages.isTriples(lang))
+        {
+            RDFFormat format = Lang.RDFXML.equals(lang) ? RDFFormat.RDFXML_PLAIN : RDFWriterRegistry.defaultSerialization(lang); // keep basic (plain) RDF/XML, not the abbreviated default
+            RDFWriter.create().
+                format(format).
+                source(dataset.getDefaultModel()).
+                output(entityStream);
+        }
         else RDFDataMgr.write(entityStream, dataset, lang);
     }
 

src/main/java/com/atomgraph/core/io/ModelProvider.java

@@ -31,9 +31,11 @@
 import jakarta.ws.rs.ext.MessageBodyWriter;
 import jakarta.ws.rs.ext.Provider;
 import org.apache.jena.riot.Lang;
+import org.apache.jena.riot.RDFFormat;
 import org.apache.jena.riot.RDFLanguages;
 import org.apache.jena.riot.RDFParser;
 import org.apache.jena.riot.RDFParserRegistry;
+import org.apache.jena.riot.RDFWriter;
 import org.apache.jena.riot.RDFWriterRegistry;
 import org.apache.jena.riot.system.ErrorHandler;
 import org.apache.jena.riot.system.ErrorHandlerFactory;
@@ -158,7 +160,12 @@ public Model write(Model model, OutputStream os, Lang lang, String baseURI)
         String syntax = lang.getName();
         if (log.isDebugEnabled()) log.debug("Syntax used to write Model: {}", syntax);
 
-        return model.write(os, syntax);
+        RDFFormat format = Lang.RDFXML.equals(lang) ? RDFFormat.RDFXML_PLAIN : RDFWriterRegistry.defaultSerialization(lang); // keep basic (plain) RDF/XML, not the abbreviated default
+        RDFWriter.create().
+            format(format).
+            source(model).
+            output(os);
+        return model;
     }
 
     public UriInfo getUriInfo()