| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you 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. |
| |
| //----------------------------------------------------------------------------- |
| // MurmurHash3 was written by Austin Appleby, and is placed in the public |
| // domain. The author hereby disclaims copyright to this source code. |
| |
| #ifndef PARQUET_MURMURHASH3_H_ |
| #define PARQUET_MURMURHASH3_H_ |
| |
| #include <cstdint> |
| |
| #include "parquet/hasher.h" |
| #include "parquet/types.h" |
| |
| namespace parquet { |
| |
| /// Source: |
| /// https://github.com/aappleby/smhasher/blob/master/src/MurmurHash3.cpp |
| /// (Modified to adapt to coding conventions and to inherit the Hasher abstract class) |
| class MurmurHash3 : public Hasher { |
| public: |
| MurmurHash3() : seed_(DEFAULT_SEED) {} |
| uint64_t Hash(int32_t value) const override; |
| uint64_t Hash(int64_t value) const override; |
| uint64_t Hash(float value) const override; |
| uint64_t Hash(double value) const override; |
| uint64_t Hash(const Int96* value) const override; |
| uint64_t Hash(const ByteArray* value) const override; |
| uint64_t Hash(const FLBA* val, uint32_t len) const override; |
| |
| private: |
| // Default seed for hash which comes from Bloom filter in parquet-mr, it is generated |
| // by System.nanoTime() of java. |
| static constexpr int DEFAULT_SEED = 1361930890; |
| |
| uint32_t seed_; |
| }; |
| |
| } // namespace parquet |
| |
| #endif // PARQUET_MURMURHASH3_H_ |