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diff --git a/bundles/org.simantics.layer0.utils/src/org/simantics/layer0/utils/binaryPredicates/CompositePredicate.java b/bundles/org.simantics.layer0.utils/src/org/simantics/layer0/utils/binaryPredicates/CompositePredicate.java
new file mode 100644
index 000000000..88000f680
--- /dev/null
+++ b/bundles/org.simantics.layer0.utils/src/org/simantics/layer0/utils/binaryPredicates/CompositePredicate.java
@@ -0,0 +1,162 @@
+/*******************************************************************************
+ * 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.Collection;
+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 CompositePredicate extends BinaryPredicate {
+	IBinaryPredicate first;
+	IBinaryPredicate second;
+	
+	int hasStatementDirection;
+	int getStatementsDirection;
+	
+	public CompositePredicate(IBinaryPredicate first, IBinaryPredicate second) {
+		this.first = first;
+		this.second = second;		
+		if(first.supportsGetStatements() && second.supportsGetObjects())
+			getStatementsDirection = 1;
+		else if(second.supportsGetStatements() && first.supportsGetSubjects())
+			getStatementsDirection = 2;
+		else
+			this.getStatementsDirection = 0;
+		if(first.supportsGetObjects())
+			hasStatementDirection = 1;
+		else if(second.supportsGetSubjects())
+			hasStatementDirection = 2;
+		else
+			throw new IllegalArgumentException("Cannot compose binary predicates such that the first one does not support getObjects and the second one does not support getSubjects.");
+	}
+
+	@Override
+	public Collection<Resource> getObjects(ReadGraph g, Resource subject) throws DatabaseException {
+		Set<Resource> result = new HashSet<Resource>();
+		for(Resource r : first.getObjects(g, subject))
+			result.addAll(second.getObjects(g, r));
+		return result;
+	}
+
+	@Override
+	public Collection<Pair<Resource, Resource>> getStatements(ReadGraph g) throws DatabaseException {
+		Set<Pair<Resource, Resource>> result = 
+			new HashSet<Pair<Resource, Resource>>();
+		if(getStatementsDirection == 1)
+			for(Pair<Resource, Resource> p : first.getStatements(g))
+				for(Resource r : second.getObjects(g, p.second))
+					result.add(new Pair<Resource, Resource>(p.first, r));
+		else if(getStatementsDirection == 2)
+			for(Pair<Resource, Resource> p : second.getStatements(g))
+				for(Resource r : second.getSubjects(g, p.first))
+					result.add(new Pair<Resource, Resource>(r, p.second));
+		else
+			throw new UnsupportedOperationException();
+		return result;
+	}
+
+	@Override
+	public Collection<Resource> getSubjects(ReadGraph g, Resource object) throws DatabaseException {
+		Set<Resource> result = new HashSet<Resource>();
+		for(Resource r : second.getSubjects(g, object))
+			result.addAll(first.getSubjects(g, r));
+		return result;
+	}
+
+	@Override
+	public boolean has(ReadGraph g, Resource subject, Resource object) throws DatabaseException {
+		if(hasStatementDirection == 1) {
+			for(Resource r : first.getObjects(g, subject))
+				if(second.has(g, r, object))
+					return true;
+		}
+		else {
+			for(Resource r : second.getSubjects(g, object))
+				if(second.has(g, subject, r))
+					return true;
+		}
+		return false;
+	}
+
+	@Override
+	public void add(WriteGraph g, Resource subject, Resource object) {
+		throw new UnsupportedOperationException();
+	}
+
+	@Override
+	public void remove(WriteGraph g, Resource subject, Resource object) {
+		throw new UnsupportedOperationException();
+	}
+
+	@Override
+	public boolean supportsAdditions() {
+		return false;
+	}
+
+	@Override
+	public boolean supportsGetObjects() {
+		return first.supportsGetObjects() && second.supportsGetObjects();
+	}
+
+	@Override
+	public boolean supportsGetStatements() {
+		return getStatementsDirection != 0;
+	}
+
+	@Override
+	public boolean supportsGetSubjects() {
+		return first.supportsGetSubjects() && second.supportsGetSubjects();
+	}
+
+	@Override
+	public boolean supportsRemovals() {		
+		return false;
+	}
+
+	@Override
+	public int hashCode() {
+		final int prime = 31;
+		int result = 1;
+		result = prime * result + ((first == null) ? 0 : first.hashCode());
+		result = prime * result + ((second == null) ? 0 : second.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;
+		CompositePredicate other = (CompositePredicate) obj;
+		if (first == null) {
+			if (other.first != null)
+				return false;
+		} else if (!first.equals(other.first))
+			return false;
+		if (second == null) {
+			if (other.second != null)
+				return false;
+		} else if (!second.equals(other.second))
+			return false;
+		return true;
+	}	
+	
+}