/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.vxquery.runtime.functions.aggregate;
import java.io.DataOutput;
import org.apache.vxquery.datamodel.accessors.TaggedValuePointable;
import org.apache.vxquery.datamodel.accessors.TypedPointables;
import org.apache.vxquery.datamodel.builders.sequence.SequenceBuilder;
import org.apache.vxquery.datamodel.values.ValueTag;
import org.apache.vxquery.datamodel.values.XDMConstants;
import org.apache.vxquery.exceptions.SystemException;
import org.apache.vxquery.runtime.functions.arithmetic.AddOperation;
import org.apache.vxquery.runtime.functions.base.AbstractTaggedValueArgumentAggregateEvaluator;
import org.apache.vxquery.runtime.functions.base.AbstractTaggedValueArgumentAggregateEvaluatorFactory;
import org.apache.vxquery.runtime.functions.util.FunctionHelper;
import edu.uci.ics.hyracks.algebricks.common.exceptions.AlgebricksException;
import edu.uci.ics.hyracks.algebricks.runtime.base.IAggregateEvaluator;
import edu.uci.ics.hyracks.algebricks.runtime.base.IScalarEvaluator;
import edu.uci.ics.hyracks.algebricks.runtime.base.IScalarEvaluatorFactory;
import edu.uci.ics.hyracks.data.std.api.IPointable;
import edu.uci.ics.hyracks.data.std.util.ArrayBackedValueStorage;
public class AvgLocalAggregateEvaluatorFactory extends AbstractTaggedValueArgumentAggregateEvaluatorFactory {
private static final long serialVersionUID = 1L;
public AvgLocalAggregateEvaluatorFactory(IScalarEvaluatorFactory[] args) {
super(args);
}
@Override
protected IAggregateEvaluator createEvaluator(IScalarEvaluator[] args) throws AlgebricksException {
final TaggedValuePointable tvpCount = (TaggedValuePointable) TaggedValuePointable.FACTORY.createPointable();
final ArrayBackedValueStorage abvsCount = new ArrayBackedValueStorage();
final DataOutput dOutCount = abvsCount.getDataOutput();
final ArrayBackedValueStorage abvsSum = new ArrayBackedValueStorage();
final DataOutput dOutSum = abvsSum.getDataOutput();
final ArrayBackedValueStorage abvsSeq = new ArrayBackedValueStorage();
final SequenceBuilder sb = new SequenceBuilder();
final AddOperation aOp = new AddOperation();
final TypedPointables tp1 = new TypedPointables();
final TypedPointables tp2 = new TypedPointables();
return new AbstractTaggedValueArgumentAggregateEvaluator(args) {
long count;
TaggedValuePointable tvpSum = (TaggedValuePointable) TaggedValuePointable.FACTORY.createPointable();
@Override
public void init() throws AlgebricksException {
count = 0;
try {
abvsSum.reset();
dOutSum.write(ValueTag.XS_INTEGER_TAG);
dOutSum.writeLong(0);
tvpSum.set(abvsSum);
} catch (Exception e) {
throw new AlgebricksException(e);
}
}
@Override
public void finishPartial(IPointable result) throws AlgebricksException {
finish(result);
}
@Override
public void finish(IPointable result) throws AlgebricksException {
if (count == 0) {
XDMConstants.setEmptySequence(result);
} else {
// Set count as a TaggedValuePointable.
try {
abvsCount.reset();
dOutCount.write(ValueTag.XS_INTEGER_TAG);
dOutCount.writeLong(count);
tvpCount.set(abvsCount);
// Save intermediate result.
abvsSeq.reset();
sb.reset(abvsSeq);
sb.addItem(tvpCount);
sb.addItem(tvpSum);
sb.finish();
result.set(abvsSeq);
} catch (Exception e) {
throw new AlgebricksException(e);
}
}
}
@Override
protected void step(TaggedValuePointable[] args) throws SystemException {
TaggedValuePointable tvp = args[0];
FunctionHelper.arithmeticOperation(aOp, dCtx, tvp, tvpSum, tvpSum, tp1, tp2);
count++;
}
};
}
}