/**
* Copyright (c) 2013, Institute of Information Systems (Sven Groppe and contributors of LUPOSDATE), University of Luebeck
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted provided that the
* following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice, this list of conditions and the following
* disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the
* following disclaimer in the documentation and/or other materials provided with the distribution.
* - Neither the name of the University of Luebeck nor the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package lupos.engine.operators.singleinput;
import java.util.Collection;
import java.util.Iterator;
import lupos.datastructures.bindings.Bindings;
import lupos.datastructures.items.Item;
import lupos.datastructures.items.Variable;
import lupos.datastructures.items.literal.Literal;
import lupos.datastructures.queryresult.ParallelIterator;
import lupos.datastructures.queryresult.QueryResult;
import lupos.engine.operators.tripleoperator.TriplePattern;
import lupos.misc.BitVector;
public class SIPFilterOperatorIterator extends SIPFilterOperator {
public SIPFilterOperatorIterator(final Collection<TriplePattern> ctp,
final Collection<Variable> vars) {
super(ctp, vars);
}
@Override
public synchronized QueryResult process(final QueryResult res,
final int operandID) {
return QueryResult.createInstance(new ParallelIterator<Bindings>() {
Iterator<Bindings> itb = res.oneTimeIterator();
public void close() {
if (itb instanceof ParallelIterator)
((ParallelIterator) itb).close();
}
public boolean hasNext() {
return itb.hasNext();
}
public Bindings next() {
final Bindings b = itb.next();
if (b != null) {
final Iterator<BitVector> ibv = bloomFilters.iterator();
for (final Variable v : vars) {
final BitVector bv = ibv.next();
Literal literal = b.get(v);
if(literal!=null){
bv.set((Math.abs(literal.hashCode()) % NUMBEROFBITSFORBLOOMFILTER));
}
}
if (!itb.hasNext()) {
for (final TriplePattern tp : ctp) {
// inform triple patterns of bloom filter!
int i = 0;
for (final Item item : tp) {
if (item.isVariable()) {
final Iterator<BitVector> ibv2 = bloomFilters
.iterator();
for (final Variable v : vars) {
final BitVector bloomFilter = ibv2
.next();
if (v.equals(item)) {
BitVector[] bfa = tp
.getBloomFilters();
if (bfa == null) {
bfa = new BitVector[3];
bfa[i] = bloomFilter;
} else {
if (bfa[i] != null) {
if (!bfa[i]
.equals(bloomFilter))
for (int j = 0; j < bloomFilter
.size(); j++)
if (!bloomFilter
.get(j))
bfa[i].clear(j);
} else
bfa[i] = bloomFilter;
}
tp.setBloomFilters(bfa);
}
}
}
i++;
}
}
}
}
return b;
}
public void remove() {
itb.remove();
}
@Override
public void finalize() {
close();
}
});
}
}