/**
* 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.sort;
import java.util.Collection;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import lupos.datastructures.bindings.Bindings;
import lupos.datastructures.dbmergesortedds.DBMergeSortedBag;
import lupos.datastructures.dbmergesortedds.SortConfiguration;
import lupos.datastructures.items.Variable;
import lupos.datastructures.items.literal.Literal;
import lupos.datastructures.queryresult.ParallelIterator;
import lupos.datastructures.queryresult.QueryResult;
import lupos.datastructures.sorteddata.SortedBag;
public class ImmediateSort extends Sort {
/**
*
*/
private static final long serialVersionUID = -6875180850101362304L;
protected Comparator<Bindings> compLocal = comparator;
protected List<Variable> sortCriterium;
public ImmediateSort() {
super();
}
public ImmediateSort(final List<Variable> sortCriterium) {
super();
this.sortCriterium = sortCriterium;
compLocal = new Comparator<Bindings>() {
public int compare(final Bindings o1, final Bindings o2) {
for (final Variable var : sortCriterium) {
final Literal l1 = o1.get(var);
final Literal l2 = o2.get(var);
if (l1 != null && l2 != null) {
final int compare = l1
.compareToNotNecessarilySPARQLSpecificationConform(l2);
if (compare != 0)
return compare;
} else if (l1 != null)
return -1;
else if (l2 != null)
return 1;
}
return 0;
}
};
}
public ImmediateSort(final lupos.sparql1_1.Node node) {
super(node);
}
public Collection<Variable> getSortCriterium() {
return sortCriterium;
}
@Override
public synchronized QueryResult process(final QueryResult bindings,
final int operandID) {
final SortedBag<Bindings> sswd = createBag();
final Iterator<Bindings> itb = bindings.oneTimeIterator();
while (itb.hasNext()) {
sswd.add(itb.next());
}
return QueryResult.createInstance(getIterator(sswd.iterator()));
}
protected SortedBag<Bindings> createBag() {
return new DBMergeSortedBag<Bindings>(new SortConfiguration(), compLocal,
Bindings.class);
}
protected ParallelIterator<Bindings> getIterator(
final Iterator<Bindings> itb) {
return new ParallelIterator<Bindings>() {
public void close() {
if (itb instanceof ParallelIterator)
((ParallelIterator<Bindings>) itb).close();
}
public boolean hasNext() {
return itb.hasNext();
}
public Bindings next() {
return itb.next();
}
public void remove() {
itb.remove();
}
};
}
}