/***********************************************************************************************************************
* Copyright (C) 2010-2013 by the Stratosphere project (http://stratosphere.eu)
*
* 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 eu.stratosphere.api.common.aggregators;
import eu.stratosphere.types.LongValue;
/**
* An {@link Aggregator} that sums up long values.
*/
public class LongSumAggregator implements Aggregator<LongValue> {
private long sum; // the sum
@Override
public LongValue getAggregate() {
return new LongValue(sum);
}
@Override
public void aggregate(LongValue element) {
sum += element.getValue();
}
/**
* Adds the given value to the current aggregate.
*
* @param value The value to add to the aggregate.
*/
public void aggregate(long value) {
sum += value;
}
@Override
public void reset() {
sum = 0;
}
}