| // 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. |
| |
| #ifndef PARQUET_RECORD_READER_H |
| #define PARQUET_RECORD_READER_H |
| |
| #include <cstdint> |
| #include <cstring> |
| #include <iostream> |
| #include <memory> |
| #include <unordered_map> |
| #include <vector> |
| |
| #include <arrow/buffer.h> |
| #include <arrow/builder.h> |
| #include <arrow/memory_pool.h> |
| #include <arrow/util/bit-util.h> |
| |
| #include "parquet/column_reader.h" |
| #include "parquet/schema.h" |
| #include "parquet/util/visibility.h" |
| |
| namespace parquet { |
| namespace internal { |
| |
| /// \brief Stateful column reader that delimits semantic records for both flat |
| /// and nested columns |
| /// |
| /// \note API EXPERIMENTAL |
| /// \since 1.3.0 |
| class RecordReader { |
| public: |
| // So that we can create subclasses |
| class RecordReaderImpl; |
| |
| static std::shared_ptr<RecordReader> Make( |
| const ColumnDescriptor* descr, |
| ::arrow::MemoryPool* pool = ::arrow::default_memory_pool()); |
| |
| virtual ~RecordReader(); |
| |
| /// \brief Decoded definition levels |
| const int16_t* def_levels() const; |
| |
| /// \brief Decoded repetition levels |
| const int16_t* rep_levels() const; |
| |
| /// \brief Decoded values, including nulls, if any |
| const uint8_t* values() const; |
| |
| /// \brief Attempt to read indicated number of records from column chunk |
| /// \return number of records read |
| int64_t ReadRecords(int64_t num_records); |
| |
| /// \brief Pre-allocate space for data. Results in better flat read performance |
| void Reserve(int64_t num_values); |
| |
| /// \brief Clear consumed values and repetition/definition levels as the |
| /// result of calling ReadRecords |
| void Reset(); |
| |
| std::shared_ptr<PoolBuffer> ReleaseValues(); |
| std::shared_ptr<PoolBuffer> ReleaseIsValid(); |
| ::arrow::ArrayBuilder* builder(); |
| |
| /// \brief Number of values written including nulls (if any) |
| int64_t values_written() const; |
| |
| /// \brief Number of definition / repetition levels (from those that have |
| /// been decoded) that have been consumed inside the reader. |
| int64_t levels_position() const; |
| |
| /// \brief Number of definition / repetition levels that have been written |
| /// internally in the reader |
| int64_t levels_written() const; |
| |
| /// \brief Number of nulls in the leaf |
| int64_t null_count() const; |
| |
| /// \brief True if the leaf values are nullable |
| bool nullable_values() const; |
| |
| /// \brief Return true if the record reader has more internal data yet to |
| /// process |
| bool HasMoreData() const; |
| |
| /// \brief Advance record reader to the next row group |
| /// \param[in] reader obtained from RowGroupReader::GetColumnPageReader |
| void SetPageReader(std::unique_ptr<PageReader> reader); |
| |
| private: |
| std::unique_ptr<RecordReaderImpl> impl_; |
| explicit RecordReader(RecordReaderImpl* impl); |
| }; |
| |
| } // namespace internal |
| } // namespace parquet |
| |
| #endif // PARQUET_RECORD_READER_H |