package org.apache.lucene.search.grouping.function;
/*
* 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.
*/
import org.apache.lucene.index.AtomicReaderContext;
import org.apache.lucene.queries.function.FunctionValues;
import org.apache.lucene.queries.function.ValueSource;
import org.apache.lucene.search.grouping.AbstractDistinctValuesCollector;
import org.apache.lucene.search.grouping.SearchGroup;
import org.apache.lucene.util.mutable.MutableValue;
import java.io.IOException;
import java.util.*;
/**
* Function based implementation of {@link org.apache.lucene.search.grouping.AbstractDistinctValuesCollector}.
*
* @lucene.experimental
*/
public class FunctionDistinctValuesCollector extends AbstractDistinctValuesCollector<FunctionDistinctValuesCollector.GroupCount> {
private final Map<?, ?> vsContext;
private final ValueSource groupSource;
private final ValueSource countSource;
private final Map<MutableValue, GroupCount> groupMap;
private FunctionValues.ValueFiller groupFiller;
private FunctionValues.ValueFiller countFiller;
private MutableValue groupMval;
private MutableValue countMval;
public FunctionDistinctValuesCollector(Map<?, ?> vsContext, ValueSource groupSource, ValueSource countSource, Collection<SearchGroup<MutableValue>> groups) {
this.vsContext = vsContext;
this.groupSource = groupSource;
this.countSource = countSource;
groupMap = new LinkedHashMap<MutableValue, GroupCount>();
for (SearchGroup<MutableValue> group : groups) {
groupMap.put(group.groupValue, new GroupCount(group.groupValue));
}
}
@Override
public List<GroupCount> getGroups() {
return new ArrayList<GroupCount>(groupMap.values());
}
@Override
public void collect(int doc) throws IOException {
groupFiller.fillValue(doc);
GroupCount groupCount = groupMap.get(groupMval);
if (groupCount != null) {
countFiller.fillValue(doc);
groupCount.uniqueValues.add(countMval.duplicate());
}
}
@Override
public void setNextReader(AtomicReaderContext context) throws IOException {
FunctionValues values = groupSource.getValues(vsContext, context);
groupFiller = values.getValueFiller();
groupMval = groupFiller.getValue();
values = countSource.getValues(vsContext, context);
countFiller = values.getValueFiller();
countMval = countFiller.getValue();
}
/** Holds distinct values for a single group.
*
* @lucene.experimental */
public static class GroupCount extends AbstractDistinctValuesCollector.GroupCount<MutableValue> {
GroupCount(MutableValue groupValue) {
super(groupValue);
}
}
}