blob: 29ded090c24937ca1383676b9823768d0b5838f0 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
|
/*******************************************************************************
* Copyright (c) 2010-2016, Gabor Bergmann, IncQueryLabs Ltd.
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0 which is available at
* http://www.eclipse.org/legal/epl-v20.html.
*
* SPDX-License-Identifier: EPL-2.0
*******************************************************************************/
package tools.refinery.viatra.runtime.matchers.aggregators;
import java.util.stream.Stream;
import tools.refinery.viatra.runtime.matchers.psystem.aggregations.AbstractMemorylessAggregationOperator;
/**
* Incrementally computes the sum of java.lang.Long values
* @author Gabor Bergmann
* @since 1.4
*/
public class LongSumOperator extends AbstractMemorylessAggregationOperator<Long, Long> {
public static final LongSumOperator INSTANCE = new LongSumOperator();
private LongSumOperator() {
// Singleton, do not call.
}
@Override
public String getShortDescription() {
return "sum<Long> incrementally computes the sum of java.lang.Long values";
}
@Override
public String getName() {
return "sum<Long>";
}
@Override
public Long createNeutral() {
return 0L;
}
@Override
public boolean isNeutral(Long result) {
return createNeutral().equals(result);
}
@Override
public Long update(Long oldResult, Long updateValue, boolean isInsertion) {
return isInsertion ?
oldResult + updateValue :
oldResult - updateValue;
}
/**
* @since 2.0
*/
@Override
public Long aggregateStream(Stream<Long> stream) {
return stream.mapToLong(Long::longValue).sum();
}
}
|