/*******************************************************************************
* Copyright (c) 2010-2012, Tamas Szabo, Gabor Bergmann, Istvan Rath and Daniel Varro
* 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:
* Tamas Szabo - initial API and implementation
*******************************************************************************/
package org.eclipse.incquery.runtime.rete.index;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
import org.eclipse.incquery.runtime.base.itc.alg.incscc.IncSCCAlg;
import org.eclipse.incquery.runtime.rete.collections.CollectionsFactory;
import org.eclipse.incquery.runtime.rete.network.Direction;
import org.eclipse.incquery.runtime.rete.network.Receiver;
import org.eclipse.incquery.runtime.rete.single.TransitiveClosureNode;
import org.eclipse.incquery.runtime.rete.tuple.FlatTuple;
import org.eclipse.incquery.runtime.rete.tuple.MaskedTuple;
import org.eclipse.incquery.runtime.rete.tuple.Tuple;
import org.eclipse.incquery.runtime.rete.tuple.TupleMask;
public class TransitiveClosureNodeIndexer extends StandardIndexer implements IterableIndexer {
private TransitiveClosureNode tcNode;
private IncSCCAlg<Object> tcAlg;
private Collection<Tuple> emptySet;
public TransitiveClosureNodeIndexer(TupleMask mask, IncSCCAlg<Object> tcAlg, TransitiveClosureNode tcNode) {
super(tcNode.getContainer(), mask);
this.tcAlg = tcAlg;
this.tcNode = tcNode;
this.emptySet = Collections.emptySet();
}
@Override
public Collection<Tuple> get(Tuple signature) {
if (signature.getSize() == mask.sourceWidth) {
if (mask.indices.length == 0) {
// mask ()/2
return getSignatures();
} else if (mask.indices.length == 1) {
Set<Tuple> retSet = CollectionsFactory.getSet();//new HashSet<Tuple>();
// mask (0)/2
if (mask.indices[0] == 0) {
Object source = signature.get(0);
for (Object target : tcAlg.getAllReachableTargets(source)) {
retSet.add(new FlatTuple(source, target));
}
return retSet;
}
// mask (1)/2
if (mask.indices[0] == 1) {
Object target = signature.get(1);
for (Object source : tcAlg.getAllReachableSources(target)) {
retSet.add(new FlatTuple(source, target));
}
return retSet;
}
} else {
// mask (0,1)/2
if (mask.indices[0] == 0 && mask.indices[1] == 1) {
Object source = signature.get(0);
Object target = signature.get(1);
Tuple singleton = new FlatTuple(new FlatTuple(source, target));
return (tcAlg.isReachable(source, target) ? Collections.singleton(singleton) : emptySet);
}
// mask (1,0)/2
if (mask.indices[0] == 1 && mask.indices[1] == 0) {
Object source = signature.get(1);
Object target = signature.get(0);
Tuple singleton = new FlatTuple(new FlatTuple(source, target));
return (tcAlg.isReachable(source, target) ? Collections.singleton(singleton) : emptySet);
}
}
}
return null;
}
public Collection<Tuple> getSignatures() {
return asTupleCollection(tcAlg.getTcRelation());
}
public Iterator<Tuple> iterator() {
return asTupleCollection(tcAlg.getTcRelation()).iterator();
}
private Collection<Tuple> asTupleCollection(
Collection<org.eclipse.incquery.runtime.base.itc.alg.misc.Tuple<Object>> tuples) {
Set<Tuple> retSet = CollectionsFactory.getSet();//new HashSet<Tuple>();
for (org.eclipse.incquery.runtime.base.itc.alg.misc.Tuple<Object> tuple : tuples) {
retSet.add(new FlatTuple(tuple.getSource(), tuple.getTarget()));
}
return retSet;
}
public void propagate(Direction direction, Tuple updateElement, boolean change) {
propagate(direction, updateElement, new MaskedTuple(updateElement, mask), change);
}
@Override
public Receiver getActiveNode() {
return tcNode;
}
}