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 // 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.
 
 #pragma once
 
 #include <memory>
 
 #include "arrow/io/type_fwd.h"
 #include "arrow/json/options.h"
 #include "arrow/record_batch.h"
 #include "arrow/result.h"
 #include "arrow/status.h"
 #include "arrow/util/macros.h"
 #include "arrow/util/type_fwd.h"
 #include "arrow/util/visibility.h"
 
 namespace arrow {
 namespace json {
 
 /// A class that reads an entire JSON file into a Arrow Table
 ///
 /// The file is expected to consist of individual line-separated JSON objects
 class ARROW_EXPORT TableReader {
  public:
   virtual ~TableReader() = default;
 
   /// Read the entire JSON file and convert it to a Arrow Table
   virtual Result<std::shared_ptr<Table>> Read() = 0;
 
   /// Create a TableReader instance
   static Result<std::shared_ptr<TableReader>> Make(MemoryPool* pool,
                                                    std::shared_ptr<io::InputStream> input,
                                                    const ReadOptions&,
                                                    const ParseOptions&);
 };
 
 ARROW_EXPORT Result<std::shared_ptr<RecordBatch>> ParseOne(ParseOptions options,
                                                            std::shared_ptr<Buffer> json);
 
 /// \brief A class that reads a JSON file incrementally
 ///
 /// JSON data is read from a stream in fixed-size blocks (configurable with
 /// `ReadOptions::block_size`). Each block is converted to a `RecordBatch`. Yielded
 /// batches have a consistent schema but may differ in row count.
 ///
 /// The supplied `ParseOptions` are used to determine a schema, based either on a
 /// provided explicit schema or inferred from the first non-empty block.
 /// Afterwards, the target schema is frozen. If `UnexpectedFieldBehavior::InferType` is
 /// specified, unexpected fields will only be inferred for the first block. Afterwards
 /// they'll be treated as errors.
 ///
 /// If `ReadOptions::use_threads` is `true`, each block's parsing/decoding task will be
 /// parallelized on the given `cpu_executor` (with readahead corresponding to the
 /// executor's capacity). If an executor isn't provided, the global thread pool will be
 /// used.
 ///
 /// If `ReadOptions::use_threads` is `false`, computations will be run on the calling
 /// thread and `cpu_executor` will be ignored.
 class ARROW_EXPORT StreamingReader : public RecordBatchReader {
  public:
   virtual ~StreamingReader() = default;
 
   /// \brief Read the next `RecordBatch` asynchronously
   /// This function is async-reentrant (but not synchronously reentrant). However, if
   /// threading is disabled, this will block until completion.
   virtual Future<std::shared_ptr<RecordBatch>> ReadNextAsync() = 0;
 
   /// Get the number of bytes which have been successfully converted to record batches
   /// and consumed
   [[nodiscard]] virtual int64_t bytes_processed() const = 0;
 
   /// \brief Create a `StreamingReader` from an `InputStream`
   /// Blocks until the initial batch is loaded
   ///
   /// \param[in] stream JSON source stream
   /// \param[in] read_options Options for reading
   /// \param[in] parse_options Options for chunking, parsing, and conversion
   /// \param[in] io_context Context for IO operations (optional)
   /// \param[in] cpu_executor Executor for computation tasks (optional)
   /// \return The initialized reader
   static Result<std::shared_ptr<StreamingReader>> Make(
       std::shared_ptr<io::InputStream> stream, const ReadOptions& read_options,
       const ParseOptions& parse_options,
       const io::IOContext& io_context = io::default_io_context(),
       ::arrow::internal::Executor* cpu_executor = NULLPTR);
 
   /// \brief Create a `StreamingReader` from an `InputStream` asynchronously
   /// Returned future completes after loading the first batch
   ///
   /// \param[in] stream JSON source stream
   /// \param[in] read_options Options for reading
   /// \param[in] parse_options Options for chunking, parsing, and conversion
   /// \param[in] io_context Context for IO operations (optional)
   /// \param[in] cpu_executor Executor for computation tasks (optional)
   /// \return Future for the initialized reader
   static Future<std::shared_ptr<StreamingReader>> MakeAsync(
       std::shared_ptr<io::InputStream> stream, const ReadOptions& read_options,
       const ParseOptions& parse_options,
       const io::IOContext& io_context = io::default_io_context(),
       ::arrow::internal::Executor* cpu_executor = NULLPTR);
 };
 
 }  // namespace json
 }  // namespace arrow

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