From a333f3b6f20b4d16e159eed4b4bbb4656b28488b Mon Sep 17 00:00:00 2001
From: Antti Villberg <antti.villberg@semantum.fi>
Date: Mon, 12 Dec 2016 11:56:51 +0200
Subject: [PATCH] An attempt to resolve this issue for good

refs #6169

Change-Id: Ia06d08568fa37b9a575f924dc35be5fe3fa1a941
---
 ...reamingTransferableGraphImportProcess.java | 20 +++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/bundles/org.simantics.graph.db/src/org/simantics/graph/db/StreamingTransferableGraphImportProcess.java b/bundles/org.simantics.graph.db/src/org/simantics/graph/db/StreamingTransferableGraphImportProcess.java
index 3d4b78977..a043e59f7 100644
--- a/bundles/org.simantics.graph.db/src/org/simantics/graph/db/StreamingTransferableGraphImportProcess.java
+++ b/bundles/org.simantics.graph.db/src/org/simantics/graph/db/StreamingTransferableGraphImportProcess.java
@@ -37,6 +37,7 @@ import org.simantics.db.VirtualGraph;
 import org.simantics.db.WriteOnlyGraph;
 import org.simantics.db.common.WriteBindings;
 import org.simantics.db.common.procedure.adapter.TransientCacheAsyncListener;
+import org.simantics.db.common.request.PossibleIndexRoot;
 import org.simantics.db.common.uri.UnescapedChildMapOfResource;
 import org.simantics.db.common.utils.Logger;
 import org.simantics.db.exception.DatabaseException;
@@ -210,7 +211,9 @@ public class StreamingTransferableGraphImportProcess implements TransferableGrap
 	
 	void prepare(ReadGraph graph) throws Exception {
 
-//		indexRoot = graph.syncRequest(new PossibleIndexRoot(((IImportAdvisor2)advisor).getTarget()));
+		Resource target = advisor.getTarget();
+		if(target != null)
+			indexRoot = graph.syncRequest(new PossibleIndexRoot(target));
 		
 		findBuiltins(graph);
 		readIdentities(graph);
@@ -316,7 +319,7 @@ public class StreamingTransferableGraphImportProcess implements TransferableGrap
 	    return resourceUtil.mayHaveResource(type);
 	}
 	
-	void findClusterSet(WriteOnlyGraph graph, Resource rootLibrary, Resource indexRoot, int[] clustering, int[] clusterSets, long[] clusters, int id) throws DatabaseException {
+	void findClusterSet(WriteOnlyGraph graph, Resource rootLibrary, int[] clustering, int[] clusterSets, long[] clusters, int id) throws DatabaseException {
 		ClusteringSupport support = graph.getService(ClusteringSupport.class);
 		if(id == Extensions.ROOT_LIBRARY_CLUSTER_SET || id == Extensions.INDEX_ROOT_CLUSTER_SET) return;
 		for(int pos=0,index=0;index<clustering.length;index++) {
@@ -326,9 +329,12 @@ public class StreamingTransferableGraphImportProcess implements TransferableGrap
 				if(handles[id] == 0) {
 					int csHandle = 0;
 					if(cs == Extensions.ROOT_LIBRARY_CLUSTER_SET) csHandle = builder.handle(rootLibrary);
-					else if(cs == Extensions.INDEX_ROOT_CLUSTER_SET) csHandle = builder.handle(indexRoot);
+					else if(cs == Extensions.INDEX_ROOT_CLUSTER_SET) {
+						if(indexRoot == null) throw new DatabaseException("No index root was available in TG import.");
+						csHandle = builder.handle(indexRoot);
+					}
 					else {
-						findClusterSet(graph, rootLibrary, indexRoot, clustering, clusterSets, clusters, cs);
+						findClusterSet(graph, rootLibrary, clustering, clusterSets, clusters, cs);
 						csHandle = handles[cs];
 					}
 					
@@ -373,7 +379,7 @@ public class StreamingTransferableGraphImportProcess implements TransferableGrap
 				
 				// Create clustering
 				for(int i=0;i<clusterSets.length;i++) {
-					findClusterSet(graph, graph.getRootLibrary(), indexRoot, clustering, clusterSets, clusters, clusterSets[i]);
+					findClusterSet(graph, graph.getRootLibrary(), clustering, clusterSets, clusters, clusterSets[i]);
 				}
 				
 				// Then create all resources
@@ -384,8 +390,10 @@ public class StreamingTransferableGraphImportProcess implements TransferableGrap
 		        	int setHandle = 0;
 					if(s == Extensions.ROOT_LIBRARY_CLUSTER_SET)
 						setHandle = builder.handle(graph.getRootLibrary());
-					else if(s == Extensions.INDEX_ROOT_CLUSTER_SET)
+					else if(s == Extensions.INDEX_ROOT_CLUSTER_SET) {
+						if(indexRoot == null) throw new DatabaseException("No index root was available in TG import.");
 						setHandle = builder.handle(indexRoot);
+					}
 					else setHandle = handles[s];
 					// Preserve clustering only for internal resources
 					if(clusters[j] != 0)
-- 
2.43.2