"Streaming approach": RDFHandler for Rio will flush the cached STMTs if a (currently hard coded) limit is reached.

rdfbean-2-#56

diff --git a/rdfbean-virtuoso/pom.xml b/rdfbean-virtuoso/pom.xml
index b410b7d..5ad612e 100644
--- a/rdfbean-virtuoso/pom.xml
+++ b/rdfbean-virtuoso/pom.xml
@@ -23,6 +23,11 @@
       <artifactId>rdfbean-core</artifactId>
       <version>${project.version}</version>
     </dependency>
+    <dependency>
+      <groupId>com.mysema.rdf</groupId>
+      <artifactId>rdfbean-sesame2</artifactId>
+      <version>${project.version}</version>
+    </dependency>
     <dependency>
       <groupId>com.openlinksw</groupId>
       <artifactId>virtjdbc4</artifactId>
diff --git a/rdfbean-virtuoso/src/main/java/com/mysema/rdfbean/virtuoso/RDFStreamingHandler.java b/rdfbean-virtuoso/src/main/java/com/mysema/rdfbean/virtuoso/RDFStreamingHandler.java
new file mode 100644
index 0000000..e1784e7
--- /dev/null
+++ b/rdfbean-virtuoso/src/main/java/com/mysema/rdfbean/virtuoso/RDFStreamingHandler.java
@@ -0,0 +1,79 @@
+package com.mysema.rdfbean.virtuoso;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.openrdf.model.Statement;
+import org.openrdf.model.impl.ValueFactoryImpl;
+import org.openrdf.rio.RDFHandler;
+import org.openrdf.rio.RDFHandlerException;
+
+import com.mysema.rdfbean.model.ID;
+import com.mysema.rdfbean.model.NODE;
+import com.mysema.rdfbean.model.RDFConnection;
+import com.mysema.rdfbean.model.STMT;
+import com.mysema.rdfbean.model.UID;
+import com.mysema.rdfbean.sesame.SesameDialect;
+
+public class RDFStreamingHandler implements RDFHandler {
+
+	private final RDFConnection connection;
+	private final UID currentContext;
+	
+	private final SesameDialect dialect;
+	private final List<STMT> statements;
+	private int currentCount;
+	
+	public RDFStreamingHandler(RDFConnection connection, UID context) {
+		this.connection = connection;
+		this.currentContext = context;
+		
+		this.dialect = new SesameDialect(ValueFactoryImpl.getInstance());
+		this.statements = new ArrayList<STMT>();
+		this.currentCount = 0;
+	}
+
+	@Override
+	public void startRDF() throws RDFHandlerException {
+		// nothing to do
+	}
+
+	@Override
+	public void endRDF() throws RDFHandlerException {
+		flushAndClearStatements();
+	}
+
+	@Override
+	public void handleNamespace(String prefix, String uri)
+			throws RDFHandlerException {
+		// nothing to do
+	}
+
+	@Override
+	public void handleStatement(Statement st) throws RDFHandlerException {
+
+		final ID subject = dialect.getID(st.getSubject());
+		final UID predicate = dialect.getUID(st.getPredicate());
+		final NODE object = dialect.getNODE(st.getObject());
+
+		statements.add(new STMT(subject, predicate, object, currentContext));
+
+		currentCount++;
+		
+		if (currentCount > 5000) {
+			flushAndClearStatements();
+		}
+	}
+
+	private void flushAndClearStatements() {
+		connection.update(null, statements);
+		statements.clear();
+		currentCount = 0;
+	}
+
+	@Override
+	public void handleComment(String comment) throws RDFHandlerException {
+		// nothing to do
+	}
+
+}
diff --git a/rdfbean-virtuoso/src/main/java/com/mysema/rdfbean/virtuoso/VirtuosoRepositoryConnection.java b/rdfbean-virtuoso/src/main/java/com/mysema/rdfbean/virtuoso/VirtuosoRepositoryConnection.java
index 0b02b6d..247c409 100644
--- a/rdfbean-virtuoso/src/main/java/com/mysema/rdfbean/virtuoso/VirtuosoRepositoryConnection.java
+++ b/rdfbean-virtuoso/src/main/java/com/mysema/rdfbean/virtuoso/VirtuosoRepositoryConnection.java
@@ -18,6 +18,11 @@ import java.util.Set;
 
 import javax.annotation.Nullable;
 
+import org.openrdf.rio.RDFFormat;
+import org.openrdf.rio.RDFHandlerException;
+import org.openrdf.rio.RDFParseException;
+import org.openrdf.rio.RDFParser;
+import org.openrdf.rio.Rio;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -484,27 +489,23 @@ public class VirtuosoRepositoryConnection implements RDFConnection {
         }
         PreparedStatement stmt = null;
         try {
-            byte[] bytes = ByteStreams.toByteArray(is);
-            if (format == Format.N3 || format == Format.TURTLE || format == Format.NTRIPLES) { // UTF-8
-            // String content = IOUtils.toString(is, format == Format.NTRIPLES ?
-            // "US-ASCII" : "UTF-8");
-                String content = new String(bytes, format == Format.NTRIPLES ? Charsets.US_ASCII : Charsets.UTF_8);
+            
+            if (format == Format.N3 || format == Format.TURTLE || format == Format.NTRIPLES) {
+
+            	byte[] bytes = ByteStreams.toByteArray(is);
+            	String content = new String(bytes, format == Format.NTRIPLES ? Charsets.US_ASCII : Charsets.UTF_8);
                 stmt = connection.prepareStatement("DB.DBA.TTLP(?,'',?,0)");
                 stmt.setString(1, content);
                 stmt.setString(2, context != null ? context.getId() : defaultGraph.getId());
+                stmt.execute();
+                
             } else if (format == Format.RDFXML) {
-                // String content = IOUtils.toString(is, "UTF-8"); // TODO :
-                // proper XML load
-                String content = new String(bytes, Charsets.UTF_8); // TODO :
-                                                                    // propert
-                                                                    // XML load
-                stmt = connection.prepareStatement("DB.DBA.RDF_LOAD_RDFXML(?,'',?,0)");
-                stmt.setString(1, content);
-                stmt.setString(2, context != null ? context.getId() : defaultGraph.getId());
+                
+            	loadRdfXml(is, context);
+            
             } else {
                 throw new IllegalArgumentException("Unsupported forma " + format);
             }
-            stmt.execute();
         } finally {
             if (stmt != null) {
                 stmt.close();
@@ -512,6 +513,28 @@ public class VirtuosoRepositoryConnection implements RDFConnection {
         }
 
     }
+    
+    private void loadRdfXml(InputStream is, @Nullable UID context) {
+    	try {
+    		
+    		UID currentContext = context != null ? context : defaultGraph;
+    		
+    		RDFParser rioParser = Rio.createParser(RDFFormat.RDFXML);
+    		rioParser.setRDFHandler(new RDFStreamingHandler(this, currentContext));
+    		
+    		// parses and adds triples
+    		rioParser.parse(is, currentContext.getId());
+    		
+    		
+    	} catch (RDFParseException e) {
+    		throw new RepositoryException(e);
+    	} catch (RDFHandlerException e) {
+    		throw new RepositoryException(e);
+    	} catch (IOException e) {
+    		throw new RepositoryException(e);
+    	}
+    }
+    
 
     private void remove(Collection<STMT> removedStatements) throws SQLException {
         verifyNotReadOnly();