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.driver.jdbc.accessor.impl.complex;
  
  import java.sql.Struct;
  import java.util.List;
  import java.util.Map;
  import java.util.function.IntSupplier;
  import java.util.stream.Collectors;
  import org.apache.arrow.driver.jdbc.accessor.ArrowFlightJdbcAccessor;
  import org.apache.arrow.driver.jdbc.accessor.ArrowFlightJdbcAccessorFactory;
  import org.apache.arrow.vector.complex.StructVector;
  import org.apache.calcite.avatica.util.StructImpl;
  
  /** Accessor for the Arrow type {@link StructVector}. */
  public class ArrowFlightJdbcStructVectorAccessor extends ArrowFlightJdbcAccessor {
  
    private final StructVector vector;
  
    public ArrowFlightJdbcStructVectorAccessor(
        StructVector vector,
        IntSupplier currentRowSupplier,
        ArrowFlightJdbcAccessorFactory.WasNullConsumer setCursorWasNull) {
      super(currentRowSupplier, setCursorWasNull);
      this.vector = vector;
    }
  
    @Override
    public Class<?> getObjectClass() {
      return Map.class;
    }
  
    @Override
    public Object getObject() {
      Map<String, ?> object = vector.getObject(getCurrentRow());
      this.wasNull = object == null;
      this.wasNullConsumer.setWasNull(this.wasNull);
  
      return object;
    }
  
    @Override
    public Struct getStruct() {
      int currentRow = getCurrentRow();
  
      this.wasNull = vector.isNull(currentRow);
      this.wasNullConsumer.setWasNull(this.wasNull);
      if (this.wasNull) {
        return null;
      }
  
      List<Object> attributes =
          vector.getChildrenFromFields().stream()
              .map(vector -> vector.getObject(currentRow))
              .collect(Collectors.toList());
  
      return new StructImpl(attributes);
    }
  }
  