content: /*
   * 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.
   */
  package org.apache.arrow.dataset.file;
  
  import org.apache.arrow.c.ArrowArrayStream;
  import org.apache.arrow.c.Data;
  import org.apache.arrow.memory.BufferAllocator;
  import org.apache.arrow.vector.ipc.ArrowReader;
  
  /**
   * JNI-based utility to write datasets into files. It internally depends on C++ static method
   * FileSystemDataset::Write.
   */
  public class DatasetFileWriter {
  
    /**
     * Write the contents of an ArrowReader as a dataset.
     *
     * @param reader the datasource for writing
     * @param format target file format
     * @param uri target file uri
     * @param maxPartitions maximum partitions to be included in written files
     * @param partitionColumns columns used to partition output files. Empty to disable partitioning
     * @param baseNameTemplate file name template used to make partitions. E.g. "dat_{i}", i is
     *     current partition ID around all written files.
     */
    public static void write(
        BufferAllocator allocator,
        ArrowReader reader,
        FileFormat format,
        String uri,
        String[] partitionColumns,
        int maxPartitions,
        String baseNameTemplate) {
      try (final ArrowArrayStream stream = ArrowArrayStream.allocateNew(allocator)) {
        Data.exportArrayStream(allocator, reader, stream);
        JniWrapper.get()
            .writeFromScannerToFile(
                stream.memoryAddress(),
                format.id(),
                uri,
                partitionColumns,
                maxPartitions,
                baseNameTemplate);
      }
    }
  
    /**
     * Write the contents of an ArrowReader as a dataset, with default partitioning settings.
     *
     * @param reader the datasource for writing
     * @param format target file format
     * @param uri target file uri
     */
    public static void write(
        BufferAllocator allocator, ArrowReader reader, FileFormat format, String uri) {
      write(allocator, reader, format, uri, new String[0], 1024, "data_{i}");
    }
  }
  