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;
  
  import java.io.File;
  import java.io.InputStream;
  import java.lang.reflect.Method;
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.List;
  import java.util.Random;
  import org.apache.arrow.util.Preconditions;
  import org.apache.avro.Schema;
  import org.apache.avro.generic.GenericData;
  import org.apache.avro.generic.GenericRecord;
  import org.apache.parquet.avro.AvroParquetWriter;
  import org.apache.parquet.hadoop.ParquetWriter;
  
  /** Utility class for writing Parquet files using Avro based tools. */
  public class ParquetWriteSupport implements AutoCloseable {
  
    private final String path;
    private final String uri;
    private final ParquetWriter<GenericRecord> writer;
    private final Schema avroSchema;
    private final List<GenericRecord> writtenRecords = new ArrayList<>();
    private final GenericRecordListBuilder recordListBuilder = new GenericRecordListBuilder();
    private final Random random = new Random();
  
    public ParquetWriteSupport(String schemaName, File outputFolder) throws Exception {
      avroSchema = getSchema(schemaName);
      path = outputFolder.getPath() + "/" + "generated-" + random.nextLong() + ".parquet";
      uri = "file://" + path;
      writer =
          AvroParquetWriter.<GenericRecord>builder(new org.apache.hadoop.fs.Path(path))
              .withSchema(avroSchema)
              .build();
    }
  
    public static Schema getSchema(String schemaName) throws Exception {
      try {
        // Attempt to use JDK 9 behavior of getting the module then the resource stream from the
        // module.
        // Note that this code is caller-sensitive.
        Method getModuleMethod = Class.class.getMethod("getModule");
        Object module = getModuleMethod.invoke(ParquetWriteSupport.class);
        Method getResourceAsStreamFromModule =
            module.getClass().getMethod("getResourceAsStream", String.class);
        try (InputStream is =
            (InputStream) getResourceAsStreamFromModule.invoke(module, "/avroschema/" + schemaName)) {
          return new Schema.Parser().parse(is);
        }
      } catch (NoSuchMethodException ex) {
        // Use JDK8 behavior.
        try (InputStream is =
            ParquetWriteSupport.class.getResourceAsStream("/avroschema/" + schemaName)) {
          return new Schema.Parser().parse(is);
        }
      }
    }
  
    public static ParquetWriteSupport writeTempFile(
        String schemaName, File outputFolder, Object... values) throws Exception {
      try (final ParquetWriteSupport writeSupport =
          new ParquetWriteSupport(schemaName, outputFolder)) {
        writeSupport.writeRecords(values);
        return writeSupport;
      }
    }
  
    public void writeRecords(Object... values) throws Exception {
      final List<GenericRecord> valueList = getRecordListBuilder().createRecordList(values);
      writeRecords(valueList);
    }
  
    public void writeRecords(List<GenericRecord> records) throws Exception {
      for (GenericRecord record : records) {
        writeRecord(record);
      }
    }
  
    public void writeRecord(GenericRecord record) throws Exception {
      writtenRecords.add(record);
      writer.write(record);
    }
  
    public String getOutputURI() {
      return uri;
    }
  
    public Schema getAvroSchema() {
      return avroSchema;
    }
  
    public GenericRecordListBuilder getRecordListBuilder() {
      return recordListBuilder;
    }
  
    public List<GenericRecord> getWrittenRecords() {
      return Collections.unmodifiableList(writtenRecords);
    }
  
    @Override
    public void close() throws Exception {
      writer.close();
    }
  
    public class GenericRecordListBuilder {
      public final List<GenericRecord> createRecordList(Object... values) {
        final int fieldCount = avroSchema.getFields().size();
        Preconditions.checkArgument(
            values.length % fieldCount == 0, "arg count of values should be divide by field number");
        final List<GenericRecord> recordList = new ArrayList<>();
        for (int i = 0; i < values.length / fieldCount; i++) {
          final GenericRecord record = new GenericData.Record(avroSchema);
          for (int j = 0; j < fieldCount; j++) {
            record.put(j, values[i * fieldCount + j]);
          }
          recordList.add(record);
        }
        return Collections.unmodifiableList(recordList);
      }
    }
  }
  