// Copyright 2016 Twitter. All rights reserved.
//
// Licensed 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 com.twitter.heron.simulator.grouping;
import java.util.LinkedList;
import java.util.List;
import com.twitter.heron.api.generated.TopologyAPI;
import com.twitter.heron.proto.system.HeronTuples;
public class FieldsGrouping extends Grouping {
private final List<Integer> fieldsGroupingIndices = new LinkedList<>();
public FieldsGrouping(TopologyAPI.InputStream inputStream,
TopologyAPI.StreamSchema schema,
List<Integer> taskIds) {
super(taskIds);
for (int i = 0; i < schema.getKeysCount(); i++) {
for (int j = 0; j < inputStream.getGroupingFields().getKeysCount(); j++) {
Boolean keysEqual = schema.getKeys(i).getKey().equals(
inputStream.getGroupingFields().getKeys(j).getKey());
if (keysEqual) {
fieldsGroupingIndices.add(i);
break;
}
}
}
}
@Override
public List<Integer> getListToSend(HeronTuples.HeronDataTuple tuple) {
List<Integer> res = new LinkedList<>();
int taskIndex = 0;
int primeNumber = 633910111;
for (Integer indices : fieldsGroupingIndices) {
taskIndex += getHashCode(tuple.getValues(indices)) % primeNumber;
}
taskIndex = taskIndex % taskIds.size();
// Make sure taskIndex is greater than 0
taskIndex = taskIndex >= 0 ? taskIndex : taskIndex + taskIds.size();
res.add(taskIds.get(taskIndex));
return res;
}
/**
* Returns a hash code value for the given Object,
* basing on customized hash method.
*
* @param o the given
* @return the hash code of the Object
*/
protected int getHashCode(Object o) {
return o.hashCode();
}
}