/**
* 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 storm.trident.operation.impl;
import backtype.storm.tuple.Fields;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import storm.trident.operation.Aggregator;
import storm.trident.operation.TridentCollector;
import storm.trident.operation.TridentOperationContext;
import storm.trident.tuple.ComboList;
import storm.trident.tuple.TridentTuple;
import storm.trident.tuple.TridentTupleView;
import storm.trident.tuple.TridentTupleView.ProjectionFactory;
public class GroupedAggregator implements Aggregator<Object[]> {
ProjectionFactory _groupFactory;
ProjectionFactory _inputFactory;
Aggregator _agg;
ComboList.Factory _fact;
Fields _inFields;
Fields _groupFields;
public GroupedAggregator(Aggregator agg, Fields group, Fields input, int outSize) {
_groupFields = group;
_inFields = input;
_agg = agg;
int[] sizes = new int[2];
sizes[0] = _groupFields.size();
sizes[1] = outSize;
_fact = new ComboList.Factory(sizes);
}
@Override
public void prepare(Map conf, TridentOperationContext context) {
_inputFactory = context.makeProjectionFactory(_inFields);
_groupFactory = context.makeProjectionFactory(_groupFields);
_agg.prepare(conf, new TridentOperationContext(context, _inputFactory));
}
@Override
public Object[] init(Object batchId, TridentCollector collector) {
return new Object[] {new GroupCollector(collector, _fact), new HashMap(), batchId};
}
@Override
public void aggregate(Object[] arr, TridentTuple tuple, TridentCollector collector) {
GroupCollector groupColl = (GroupCollector) arr[0];
Map<List, Object> val = (Map) arr[1];
TridentTuple group = _groupFactory.create((TridentTupleView) tuple);
TridentTuple input = _inputFactory.create((TridentTupleView) tuple);
Object curr;
if(!val.containsKey(group)) {
curr = _agg.init(arr[2], groupColl);
val.put((List) group, curr);
} else {
curr = val.get(group);
}
groupColl.currGroup = group;
_agg.aggregate(curr, input, groupColl);
}
@Override
public void complete(Object[] arr, TridentCollector collector) {
Map<List, Object> val = (Map) arr[1];
GroupCollector groupColl = (GroupCollector) arr[0];
for(Entry<List, Object> e: val.entrySet()) {
groupColl.currGroup = e.getKey();
_agg.complete(e.getValue(), groupColl);
}
}
@Override
public void cleanup() {
_agg.cleanup();
}
}