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diff --git a/bundles/org.simantics.layer0.utils/src/org/simantics/layer0/utils/binaryPredicates/TransitiveClosure.java b/bundles/org.simantics.layer0.utils/src/org/simantics/layer0/utils/binaryPredicates/TransitiveClosure.java
new file mode 100644
index 000000000..d273e6516
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+++ b/bundles/org.simantics.layer0.utils/src/org/simantics/layer0/utils/binaryPredicates/TransitiveClosure.java
@@ -0,0 +1,140 @@
+/*******************************************************************************
+ * Copyright (c) 2007, 2010 Association for Decentralized Information Management
+ * in Industry THTH ry.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     VTT Technical Research Centre of Finland - initial API and implementation
+ *******************************************************************************/
+package org.simantics.layer0.utils.binaryPredicates;
+
+import java.util.ArrayDeque;
+import java.util.Collection;
+import java.util.Deque;
+import java.util.HashSet;
+import java.util.Set;
+
+import org.simantics.db.Resource;
+import org.simantics.db.ReadGraph;
+import org.simantics.db.WriteGraph;
+import org.simantics.db.exception.DatabaseException;
+import org.simantics.utils.datastructures.Pair;
+
+public class TransitiveClosure extends BinaryPredicate {
+	IBinaryPredicate predicate;
+	
+
+	public TransitiveClosure(IBinaryPredicate predicate) {
+		this.predicate = predicate;
+	}
+
+	@Override
+	public void add(WriteGraph g, Resource subject, Resource object) throws DatabaseException {
+		if(!has(g, subject, object))
+			predicate.add(g, subject, object);
+	}
+
+	@Override
+	public Collection<Resource> getObjects(ReadGraph g, Resource subject) throws DatabaseException {
+		Deque<Resource> unprocessed = new ArrayDeque<Resource>();
+		unprocessed.add(subject);
+		Set<Resource> result = new HashSet<Resource>();
+		while(!unprocessed.isEmpty())
+			for(Resource r : predicate.getObjects(g, unprocessed.pop()))
+				if(result.add(r))
+					unprocessed.push(r);
+		return result;
+	}
+
+	@Override
+	public Collection<Pair<Resource, Resource>> getStatements(ReadGraph g) {
+		// TODO Auto-generated method stub
+		return null;
+	}
+
+	@Override
+	public Collection<Resource> getSubjects(ReadGraph g, Resource object) throws DatabaseException {
+		Deque<Resource> unprocessed = new ArrayDeque<Resource>();
+		unprocessed.add(object);
+		Set<Resource> result = new HashSet<Resource>();
+		while(!unprocessed.isEmpty())
+			for(Resource r : predicate.getSubjects(g, unprocessed.pop()))
+				if(result.add(r))
+					unprocessed.push(r);
+		return result;
+	}
+
+	@Override
+	public boolean has(ReadGraph g, Resource subject, Resource object) throws DatabaseException {
+		Deque<Resource> unprocessed = new ArrayDeque<Resource>();
+		unprocessed.add(subject);
+		Set<Resource> objects = new HashSet<Resource>();
+		while(!unprocessed.isEmpty())
+			for(Resource r : predicate.getObjects(g, unprocessed.pop()))
+				if(r.equals(object))
+					return true;
+				else if(objects.add(r))
+					unprocessed.push(r);
+		return false;
+	}
+
+	@Override
+	public void remove(WriteGraph g, Resource subject, Resource object) {
+		throw new UnsupportedOperationException();
+	}
+
+	@Override
+	public boolean supportsAdditions() {
+		return predicate.supportsAdditions();
+	}
+
+	@Override
+	public boolean supportsGetObjects() {
+		return predicate.supportsGetObjects();
+	}
+
+	@Override
+	public boolean supportsGetStatements() {
+		return false; // FIXME: just unimplemented
+	}
+
+	@Override
+	public boolean supportsGetSubjects() {
+		return predicate.supportsGetSubjects();
+	}
+
+	@Override
+	public boolean supportsRemovals() {
+		return false;
+	}
+
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result
+				+ ((predicate == null) ? 0 : predicate.hashCode());
+		return result;
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		if (this == obj)
+			return true;
+		if (obj == null)
+			return false;
+		if (getClass() != obj.getClass())
+			return false;
+		TransitiveClosure other = (TransitiveClosure) obj;
+		if (predicate == null) {
+			if (other.predicate != null)
+				return false;
+		} else if (!predicate.equals(other.predicate))
+			return false;
+		return true;
+	}
+	
+}