JENA-1233: Serializable for Node/Triple/Quad.

jena-arq/src/main/java/org/apache/jena/riot/system/InitRIOT.java

@@ -27,6 +27,7 @@ public class InitRIOT implements JenaSubsystemLifecycle {
     @Override
     public void start() {
         RIOT.init();
+        SerializerRDF.init();
     }
 
     @Override

jena-arq/src/main/java/org/apache/jena/riot/system/SNode.java

@@ -0,0 +1,53 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.riot.system;
+
+import java.io.IOException;
+import java.io.ObjectStreamException;
+import java.io.Serializable;
+
+import org.apache.jena.graph.Node;
+import org.apache.jena.riot.thrift.TRDF;
+import org.apache.jena.riot.thrift.wire.RDF_Term;
+import org.apache.thrift.protocol.TProtocol;
+
+/** Serialization of a {@link Node} using Thrift for the serialization. */  
+public final class SNode implements Serializable {
+    private static final long serialVersionUID = 0xb17aa042f299adb9L;
+    private transient Node node;
+
+    public SNode(Node node) { this.node = node; }
+    public Node getNode()   { return node; }
+
+    private void writeObject(java.io.ObjectOutputStream out) throws IOException {
+        TProtocol protocol = TRDF.protocol(out);
+        RDF_Term tterm  = new RDF_Term();
+        SerializerRDF.write(protocol, tterm, node);
+        TRDF.flush(protocol);
+    }
+
+    private void readObject(java.io.ObjectInputStream in) throws IOException {
+        TProtocol protocol = TRDF.protocol(in);
+        RDF_Term tterm  = new RDF_Term();
+        node = SerializerRDF.read(protocol, tterm);
+    }
+
+    Object readResolve() throws ObjectStreamException
+    { return node; }
+}

jena-arq/src/main/java/org/apache/jena/riot/system/SQuad.java

@@ -0,0 +1,62 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.riot.system;
+
+import java.io.IOException;
+import java.io.ObjectStreamException;
+import java.io.Serializable;
+
+import org.apache.jena.graph.Node;
+import org.apache.jena.riot.thrift.TRDF;
+import org.apache.jena.riot.thrift.wire.RDF_Term;
+import org.apache.jena.sparql.core.Quad;
+import org.apache.thrift.protocol.TProtocol;
+
+/** Serialization of a {@link Quad} using Thrift for the serialization. */  
+public final class SQuad implements Serializable {
+    private static final long serialVersionUID = 0x993530716d72ff06L;
+    private transient Quad quad;
+
+    public SQuad(Quad quad)     { this.quad = quad; }
+    public Quad getQuad()       { return quad; }
+
+    private void writeObject(java.io.ObjectOutputStream out) throws IOException {
+        TProtocol protocol = TRDF.protocol(out);
+        RDF_Term tterm  = new RDF_Term();
+        SerializerRDF.write(protocol, tterm, quad.getGraph());
+        SerializerRDF.write(protocol, tterm, quad.getSubject());
+        SerializerRDF.write(protocol, tterm, quad.getPredicate());
+        SerializerRDF.write(protocol, tterm, quad.getObject());
+        TRDF.flush(protocol);
+    }
+
+    private void readObject(java.io.ObjectInputStream in) throws IOException {
+        TProtocol protocol = TRDF.protocol(in);
+        RDF_Term tterm  = new RDF_Term();
+        Node g = SerializerRDF.read(protocol, tterm);
+        Node s = SerializerRDF.read(protocol, tterm); 
+        Node p = SerializerRDF.read(protocol, tterm);
+        Node o = SerializerRDF.read(protocol, tterm);
+        quad = Quad.create(g, s, p, o);
+    }
+
+    Object readResolve() throws ObjectStreamException
+    { return quad; }
+
+}

jena-arq/src/main/java/org/apache/jena/riot/system/STriple.java

@@ -0,0 +1,59 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.riot.system;
+
+import java.io.IOException;
+import java.io.ObjectStreamException;
+import java.io.Serializable;
+
+import org.apache.jena.graph.Node;
+import org.apache.jena.graph.Triple;
+import org.apache.jena.riot.thrift.TRDF;
+import org.apache.jena.riot.thrift.wire.RDF_Term;
+import org.apache.thrift.protocol.TProtocol;
+
+/** Serialization of a {@link Triple} using Thrift for the serialization. */  
+public final class STriple implements Serializable {
+    private static final long serialVersionUID = 0xa08f3324dc69187dL;
+    private transient Triple triple;
+
+    public STriple(Triple triple)   { this.triple = triple; }
+    public Triple getTriple()       { return triple; }
+
+    private void writeObject(java.io.ObjectOutputStream out) throws IOException {
+        TProtocol protocol = TRDF.protocol(out);
+        RDF_Term tterm  = new RDF_Term();
+        SerializerRDF.write(protocol, tterm, triple.getSubject());
+        SerializerRDF.write(protocol, tterm, triple.getPredicate());
+        SerializerRDF.write(protocol, tterm, triple.getObject());
+        TRDF.flush(protocol);
+    }
+
+    private void readObject(java.io.ObjectInputStream in) throws IOException {
+        TProtocol protocol = TRDF.protocol(in);
+        RDF_Term tterm  = new RDF_Term();
+        Node s = SerializerRDF.read(protocol, tterm); 
+        Node p = SerializerRDF.read(protocol, tterm);
+        Node o = SerializerRDF.read(protocol, tterm);
+        triple = Triple.create(s, p, o);
+    }
+
+    Object readResolve() throws ObjectStreamException
+    { return triple; }
+}

jena-arq/src/main/java/org/apache/jena/riot/system/Serializer.java

@@ -0,0 +1,58 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.riot.system;
+
+import java.io.Serializable;
+import java.util.function.Function;
+
+import org.apache.jena.sparql.core.Quad;
+
+/** The injection point for the Quad {@link Serializable} process. 
+ * This class is public to allow system initialization to inject
+ * handler functions for {@link Quad}.
+ * 
+ * See also {@code Node} and {@ocde Triple}.  
+ */
+public class Serializer {
+    /*package*/ static Function<Quad, Object> quadWriteReplaceFunction = null;
+
+    /** Set the quad serializer replacement function.
+     * This is a function called by {@code Triple.writeReplace} during the {@link Serializable} process.
+     * The return is an object used in place of {@link Quad} for the serialization.  
+     * 
+     * <PRE>
+     * ANY-ACCESS-MODIFIER Object writeReplace() throws ObjectStreamException;
+     * </PRE><p>
+     * The returned object must provide
+     * <PRE>
+     * ANY-ACCESS-MODIFIER Object readResolve() throws ObjectStreamException;
+     * </PRE><p>  
+     * where "Object" is a {@link Quad}.
+     *
+     * @see java.io.Serializable
+     */
+    public static void setQuadSerializer(Function<Quad, Object> writeReplaceFunction) {
+        quadWriteReplaceFunction = writeReplaceFunction;
+    }
+
+    /** Return the current triple serializer replacement function. */
+    public static Function<Quad, Object> getQuadSerializer() {
+        return quadWriteReplaceFunction;
+    }
+}

jena-arq/src/main/java/org/apache/jena/riot/system/SerializerRDF.java

@@ -0,0 +1,73 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.jena.riot.system;
+
+import org.apache.jena.graph.Node;
+import org.apache.jena.riot.thrift.TRDF;
+import org.apache.jena.riot.thrift.ThriftConvert;
+import org.apache.jena.riot.thrift.wire.RDF_Term;
+import org.apache.thrift.TException;
+import org.apache.thrift.protocol.TProtocol;
+
+public class SerializerRDF {
+
+    public static void init() {
+        org.apache.jena.system.Serializer.setNodeSerializer(SNode::new);
+        org.apache.jena.system.Serializer.setTripleSerializer(STriple::new);
+        org.apache.jena.riot.system.Serializer.setQuadSerializer(SQuad::new);
+    }
+
+    /* <PRE>
+    * ANY-ACCESS-MODIFIER Object writeReplace() throws ObjectStreamException;
+    * </PRE><p>
+    *
+    * This writeReplace method is invoked by serialization if the method
+    * exists and it would be accessible from a method defined within the
+    * class of the object being serialized. Thus, the method can have private,
+    * protected and package-private access. Subclass access to this method
+    * follows java accessibility rules. <p>
+    *
+    * Classes that need to designate a replacement when an instance of it
+    * is read from the stream should implement this special method with the
+    * exact signature.
+    *
+    * <PRE>
+    * ANY-ACCESS-MODIFIER Object readResolve() throws ObjectStreamException;
+    * </PRE><p>
+    */
+
+    static Node read(TProtocol protocol, RDF_Term tterm) {
+        tterm.clear();
+        try { tterm.read(protocol); }
+        catch (TException e) { TRDF.exception(e); }
+        return ThriftConvert.convert(tterm);
+    }
+
+    // For now - no prefix map, no value encoding.  
+    // The benefit unclear, sometimes even a bit slower (few percent).
+    private static final PrefixMap pmap = null;
+    private static final boolean encodeValues = false;
+
+    static void write(TProtocol protocol, RDF_Term tterm, Node node) {
+        tterm.clear();
+        ThriftConvert.toThrift(node, pmap, tterm, encodeValues);
+        try { tterm.write(protocol); }
+        catch (TException e) { TRDF.exception(e); }
+    }
+}

jena-arq/src/main/java/org/apache/jena/sparql/core/Quad.java

@@ -18,14 +18,19 @@
 
 package org.apache.jena.sparql.core;
 
+import java.io.IOException;
+import java.io.ObjectStreamException;
+import java.io.Serializable;
 import java.util.Objects;
+import java.util.function.Function;
 
 import org.apache.jena.graph.Node ;
 import org.apache.jena.graph.NodeFactory ;
 import org.apache.jena.graph.Triple ;
+import org.apache.jena.riot.system.Serializer;
 
-public class Quad
-{
+public class Quad implements Serializable 
+{    
     // Create QuadNames? GraphNames?
 
     /** Name of the default for explict use in GRAPH */
@@ -163,6 +168,22 @@ public boolean isLegalAsData()
         return true ;
     }
 
+    // ---- Serializable
+    protected Object writeReplace() throws ObjectStreamException {
+        Function<Quad, Object> function =  Serializer.getQuadSerializer() ;
+        if ( function == null )
+            throw new IllegalStateException("Function for Quad.writeReplace not set") ;
+        return function.apply(this);
+    }
+    // Any attempt to serialize without replacement is an error.
+    private void writeObject(java.io.ObjectOutputStream out) throws IOException {
+        throw new IllegalStateException(); 
+    }
+    private void readObject(java.io.ObjectInputStream in) throws IOException, ClassNotFoundException {
+        throw new IllegalStateException();
+    }
+    // ---- Serializable
+
     @Override
     public int hashCode() 
     { 

jena-arq/src/test/java/org/apache/jena/riot/system/TS_RiotSystem.java

@@ -45,7 +45,8 @@
     , TestIO_JenaWriters.class
     , TestLangRegistration.class
     , TestFormatRegistration.class
-    , TestJsonLDReadWrite.class         // Some simple testing of the jsonld-java engine. 
+    , TestJsonLDReadWrite.class         // Some simple testing of the jsonld-java engine.
+    , TestSerializable.class
 
     // May be subject to performance vagaries, with the improvements made
     // to the fast implementation this should be fairly safe