mirror of https://gitee.com/bigwinds/arangodb
59 lines
1.8 KiB
C++
59 lines
1.8 KiB
C++
////////////////////////////////////////////////////////////////////////////////
|
|
/// DISCLAIMER
|
|
///
|
|
/// Copyright 2016 ArangoDB GmbH, Cologne, Germany
|
|
///
|
|
/// 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.
|
|
///
|
|
/// Copyright holder is ArangoDB GmbH, Cologne, Germany
|
|
///
|
|
/// @author Simon Grätzer
|
|
////////////////////////////////////////////////////////////////////////////////
|
|
|
|
#include <cstdint>
|
|
|
|
#ifndef ARANGODB_PREGEL_COMBINER_H
|
|
#define ARANGODB_PREGEL_COMBINER_H 1
|
|
namespace arangodb {
|
|
namespace pregel {
|
|
|
|
// specify serialization, whatever
|
|
template <class M>
|
|
struct MessageCombiner {
|
|
virtual ~MessageCombiner() {}
|
|
virtual void combine(M& firstValue, M const& secondValue) const = 0;
|
|
};
|
|
|
|
template <typename M>
|
|
struct MinCombiner : public MessageCombiner<M> {
|
|
static_assert(std::is_arithmetic<M>::value, "Message type must be numeric");
|
|
MinCombiner() {}
|
|
void combine(M& firstValue, M const& secondValue) const override {
|
|
if (firstValue > secondValue) {
|
|
firstValue = secondValue;
|
|
}
|
|
};
|
|
};
|
|
|
|
template <typename M>
|
|
struct SumCombiner : public MessageCombiner<M> {
|
|
static_assert(std::is_arithmetic<M>::value, "Message type must be numeric");
|
|
SumCombiner() {}
|
|
void combine(M& firstValue, M const& secondValue) const override {
|
|
firstValue += secondValue;
|
|
}
|
|
};
|
|
} // namespace pregel
|
|
} // namespace arangodb
|
|
#endif
|