+package org.simantics.db.tests.api.support.virtualGraphSupport;
+
+import org.simantics.db.ReadGraph;
+import org.simantics.db.RequestProcessor;
+import org.simantics.db.Resource;
+import org.simantics.db.Session;
+import org.simantics.db.Statement;
+import org.simantics.db.VirtualGraph;
+import org.simantics.db.WriteGraph;
+import org.simantics.db.common.request.ReadRequest;
+import org.simantics.db.common.request.WriteRequest;
+import org.simantics.db.common.request.WriteResultRequest;
+import org.simantics.db.common.utils.NameUtils;
+import org.simantics.db.exception.DatabaseException;
+import org.simantics.db.service.VirtualGraphSupport;
+import org.simantics.layer0.Layer0;
+
+/**
+ * Not really created into a proper test, more a demonstration that is available
+ * in <a href="http://dev.simantics.org/index.php/Virtual_Graphs">the Simantics
+ * developer wiki</a>.
+ *
+ * @author Tuukka Lehtonen
+ */
+public class VirtualGraphExample {
+
+ public Resource createLibrary(RequestProcessor processor, VirtualGraph vg, final String libraryName) throws DatabaseException {
+ return processor.syncRequest(new WriteResultRequest<Resource>(vg) {
+ @Override
+ public Resource perform(WriteGraph graph) throws DatabaseException {
+ Layer0 L0 = Layer0.getInstance(graph);
+ Resource r = graph.newResource();
+ graph.claim(r, L0.InstanceOf, null, L0.Library);
+ graph.claimLiteral(r, L0.HasName, libraryName);
+ return r;
+ }
+ });
+ }
+
+ public void testVirtualGraphs(Session session) throws DatabaseException {
+ VirtualGraphSupport vgSupport = session.getService(VirtualGraphSupport.class);
+ VirtualGraph memory = vgSupport.getMemoryPersistent("memory");
+ VirtualGraph workspace = vgSupport.getWorkspacePersistent("workspace");
+ // NOTICE: resource are created in difference virtual graphs in separate
+ // transactions through Session.syncRequest.
+ Resource memResource = createLibrary(session, memory, "memory");
+ Resource workspaceResource = createLibrary(session, workspace, "workspace");
+ printVirtualGraphs(session);
+ }
+
+ public void testMultipleVirtualGraphsInSameTransaction(Session session) throws DatabaseException {
+ final VirtualGraphSupport vgSupport = session.getService(VirtualGraphSupport.class);
+ session.syncRequest(new WriteRequest() {
+ @Override
+ public void perform(WriteGraph graph) throws DatabaseException {
+ VirtualGraph memory = vgSupport.getMemoryPersistent("memory");
+ VirtualGraph workspace = vgSupport.getWorkspacePersistent("workspace");
+ // NOTICE: resource are created in different virtual graphs in
+ // the same transaction through WriteGraph.syncRequest
+ Resource memResource = createLibrary(graph, memory, "memory");
+ Resource workspaceResource = createLibrary(graph, workspace, "workspace");
+ }
+ });
+ printVirtualGraphs(session);
+ }
+
+ public void printVirtualGraphs(Session session) throws DatabaseException {
+ session.syncRequest(new ReadRequest() {
+ @Override
+ public void run(ReadGraph graph) throws DatabaseException {
+ VirtualGraphSupport vgSupport = graph.getService(VirtualGraphSupport.class);
+ for (VirtualGraph vg : vgSupport.listGraphs()) {
+ for (Statement stm : vgSupport.listStatements(vg)) {
+ System.out.println("Statement: " + NameUtils.toString(graph, stm));
+ }
+ for (Resource r : vgSupport.listValues(vg)) {
+ System.out.println("Literal value: " + graph.getValue(r));
+ }
+ }
+ }
+ });
+ }
+
+}