mirror of https://gitee.com/bigwinds/arangodb
59 lines
1.8 KiB
C++
59 lines
1.8 KiB
C++
////////////////////////////////////////////////////////////////////////////////
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/// DISCLAIMER
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///
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/// Copyright 2016 ArangoDB GmbH, Cologne, Germany
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///
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/// Licensed under the Apache License, Version 2.0 (the "License");
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/// you may not use this file except in compliance with the License.
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/// You may obtain a copy of the License at
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///
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/// http://www.apache.org/licenses/LICENSE-2.0
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///
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/// Unless required by applicable law or agreed to in writing, software
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/// distributed under the License is distributed on an "AS IS" BASIS,
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/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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/// See the License for the specific language governing permissions and
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/// limitations under the License.
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///
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/// Copyright holder is ArangoDB GmbH, Cologne, Germany
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///
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/// @author Simon Grätzer
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////////////////////////////////////////////////////////////////////////////////
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#include <cstdint>
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#ifndef ARANGODB_PREGEL_COMBINER_H
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#define ARANGODB_PREGEL_COMBINER_H 1
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namespace arangodb {
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namespace pregel {
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// specify serialization, whatever
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template <class M>
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struct MessageCombiner {
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virtual ~MessageCombiner() = default;
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virtual void combine(M& firstValue, M const& secondValue) const = 0;
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};
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template <typename M>
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struct MinCombiner : public MessageCombiner<M> {
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static_assert(std::is_arithmetic<M>::value, "Message type must be numeric");
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MinCombiner() {}
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void combine(M& firstValue, M const& secondValue) const override {
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if (firstValue > secondValue) {
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firstValue = secondValue;
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}
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};
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};
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template <typename M>
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struct SumCombiner : public MessageCombiner<M> {
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static_assert(std::is_arithmetic<M>::value, "Message type must be numeric");
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SumCombiner() {}
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void combine(M& firstValue, M const& secondValue) const override {
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firstValue += secondValue;
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}
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};
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} // namespace pregel
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} // namespace arangodb
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#endif
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