/**
* 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.stream;
import java.util.Date;
import java.util.LinkedList;
import lupos.datastructures.items.TimestampedTriple;
import lupos.datastructures.items.Triple;
import lupos.datastructures.items.literal.Literal;
import lupos.engine.operators.messages.Message;
import lupos.engine.operators.messages.StartOfEvaluationMessage;
import lupos.misc.debug.DebugStep;
import lupos.rdf.Prefix;
public class WindowInstancesNumber extends WindowInstances {
private int numberOfInstances = 0;
public WindowInstancesNumber(final int numberOfInstances, Literal instanceClass) {
super(instanceClass);
if (numberOfInstances < 1) {
System.err.println("X must be >=1 for WINDOW TYPE SLIDINGTRIPLES X");
System.err.println("Assuming WINDOW TYPE SLIDINGTRIPLES 1...");
this.numberOfInstances = 1;
} else
this.numberOfInstances = numberOfInstances;
}
@Override
public Message preProcessMessage(final StartOfEvaluationMessage message) {
this.tripleBuffer = new LinkedList<TimestampedTriple>();
this.typeTripleBuffer = new LinkedList<TimestampedTriple>();
return message;
}
@Override
public void consume(final Triple triple) {
final TimestampedTriple t = new TimestampedTriple(triple, (new Date()).getTime());
if(isMatchingTypeTriple(t)) {
// consume type-triple
super.consume(t);
// search for triples with same subject to consume
for(Triple tmp : this.tripleBuffer) {
if(haveSameSubject(tmp,t)) {
super.consume(tmp);
}
}
// add type triple to extra buffer
this.typeTripleBuffer.addLast(t);
// keep only the last n type-triples
if(this.typeTripleBuffer.size() > this.numberOfInstances) {
TimestampedTriple removedTypeTriple = this.typeTripleBuffer.removeFirst();
// delete old triples
// 1. delete instance of the removed type-triple
this.deleteInstance(removedTypeTriple);
// 2. delete all triples that are at least as old as the removed type-triple
while(!this.tripleBuffer.isEmpty() && this.tripleBuffer.peekFirst().getTimestamp() <= removedTypeTriple.getTimestamp()) {
TimestampedTriple tmp = this.tripleBuffer.removeFirst();
//System.out.println("delete: " + tmp.toString());
super.deleteTriple(tmp);
}
}
} else {
// consume triple if a type-triple with same subject exists
for(Triple tmp : this.typeTripleBuffer) {
if(haveSameSubject(tmp,t)) {
//System.out.println("consume: " + t.toString());
super.consume(t);
break;
}
}
}
this.tripleBuffer.addLast(t);
}
@Override
public void consumeDebug(final Triple triple, final DebugStep debugstep) {
final TimestampedTriple t = new TimestampedTriple(triple, (new Date()).getTime());
if(isMatchingTypeTriple(t)) {
// consume type-triple
super.consumeDebug(t, debugstep);
// search for triples with same subject to consume
for(Triple tmp : this.tripleBuffer) {
if(haveSameSubject(tmp,t)) {
super.consumeDebug(tmp, debugstep);
}
}
// add type triple to extra buffer
this.typeTripleBuffer.addLast(t);
// keep only the last n type-triples
if(this.typeTripleBuffer.size() > this.numberOfInstances) {
TimestampedTriple removedTypeTriple = this.typeTripleBuffer.removeFirst();
// delete old triples
// 1. delete instance of the removed type-triple
this.deleteInstanceDebug(removedTypeTriple, debugstep);
// 2. delete all triples that are at least as old as the removed type-triple
while(!this.tripleBuffer.isEmpty() && this.tripleBuffer.peekFirst().getTimestamp() <= removedTypeTriple.getTimestamp()) {
TimestampedTriple tmp = this.tripleBuffer.removeFirst();
//System.out.println("delete: " + tmp.toString());
super.deleteTripleDebug(tmp, debugstep);
}
}
} else {
// consume triple if a type-triple with same subject exists
for(Triple tmp : this.typeTripleBuffer) {
if(haveSameSubject(tmp,t)) {
//System.out.println("consume: " + t.toString());
super.consumeDebug(t, debugstep);
break;
}
}
}
this.tripleBuffer.addLast(t);
}
@Override
public String toString() {
return super.toString() + this.numberOfInstances;
}
@Override
public String toString(Prefix prefixInstance) {
return super.toString(prefixInstance) + " " + this.numberOfInstances;
}
}