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.adapter.avro.producers.logical;
  
  import java.io.IOException;
  import java.math.BigDecimal;
  import org.apache.arrow.adapter.avro.producers.BaseAvroProducer;
  import org.apache.arrow.vector.DecimalVector;
  import org.apache.arrow.vector.util.DecimalUtility;
  import org.apache.avro.io.Encoder;
  
  /**
   * Producer that produces decimal values from a {@link DecimalVector}, writes data to an Avro
   * encoder.
   */
  public class AvroDecimalProducer extends BaseAvroProducer<DecimalVector> {
  
    // Arrow stores decimals with native endianness, but Avro requires big endian
    // Writing the Arrow representation as fixed bytes fails on little-end machines
    // Instead, we replicate the big endian logic explicitly here
    // See DecimalUtility.writeByteArrayToArrowBufHelper
  
    byte[] encodedBytes = new byte[DecimalVector.TYPE_WIDTH];
  
    /** Instantiate an AvroDecimalProducer. */
    public AvroDecimalProducer(DecimalVector vector) {
      super(vector);
    }
  
    @Override
    public void produce(Encoder encoder) throws IOException {
      // Use getObject() to go back to a BigDecimal then re-encode
      BigDecimal value = vector.getObject(currentIndex++);
      encodeDecimal(value, encodedBytes);
      encoder.writeFixed(encodedBytes);
    }
  
    static void encodeDecimal(BigDecimal value, byte[] encodedBytes) {
      byte[] valueBytes = value.unscaledValue().toByteArray();
      byte[] padding = valueBytes[0] < 0 ? DecimalUtility.minus_one : DecimalUtility.zeroes;
      System.arraycopy(padding, 0, encodedBytes, 0, encodedBytes.length - valueBytes.length);
      System.arraycopy(
          valueBytes, 0, encodedBytes, encodedBytes.length - valueBytes.length, valueBytes.length);
    }
  }
  