TimeConsumer.java

/*
 * 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.jdbc.consumer;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Time;
import java.util.Calendar;
import org.apache.arrow.vector.TimeMilliVector;

/**
 * Consumer which consume time type values from {@link ResultSet}. Write the data to {@link
 * org.apache.arrow.vector.TimeMilliVector}.
 */
public abstract class TimeConsumer {

  /** Creates a consumer for {@link TimeMilliVector}. */
  public static JdbcConsumer<TimeMilliVector> createConsumer(
      TimeMilliVector vector, int index, boolean nullable, Calendar calendar) {
    if (nullable) {
      return new NullableTimeConsumer(vector, index, calendar);
    } else {
      return new NonNullableTimeConsumer(vector, index, calendar);
    }
  }

  /** Nullable consumer for {@link TimeMilliVector}. */
  static class NullableTimeConsumer extends BaseConsumer<TimeMilliVector> {

    protected final Calendar calendar;

    /** Instantiate a TimeConsumer. */
    public NullableTimeConsumer(TimeMilliVector vector, int index) {
      this(vector, index, /* calendar */ null);
    }

    /** Instantiate a TimeConsumer. */
    public NullableTimeConsumer(TimeMilliVector vector, int index, Calendar calendar) {
      super(vector, index);
      this.calendar = calendar;
    }

    @Override
    public void consume(ResultSet resultSet) throws SQLException {
      Time time =
          calendar == null
              ? resultSet.getTime(columnIndexInResultSet)
              : resultSet.getTime(columnIndexInResultSet, calendar);
      if (!resultSet.wasNull()) {
        // for fixed width vectors, we have allocated enough memory proactively,
        // so there is no need to call the setSafe method here.
        vector.set(currentIndex, (int) time.getTime());
      }
      currentIndex++;
    }
  }

  /** Non-nullable consumer for {@link TimeMilliVector}. */
  static class NonNullableTimeConsumer extends BaseConsumer<TimeMilliVector> {

    protected final Calendar calendar;

    /** Instantiate a TimeConsumer. */
    public NonNullableTimeConsumer(TimeMilliVector vector, int index) {
      this(vector, index, /* calendar */ null);
    }

    /** Instantiate a TimeConsumer. */
    public NonNullableTimeConsumer(TimeMilliVector vector, int index, Calendar calendar) {
      super(vector, index);
      this.calendar = calendar;
    }

    @Override
    public void consume(ResultSet resultSet) throws SQLException {
      Time time =
          calendar == null
              ? resultSet.getTime(columnIndexInResultSet)
              : resultSet.getTime(columnIndexInResultSet, calendar);
      // for fixed width vectors, we have allocated enough memory proactively,
      // so there is no need to call the setSafe method here.
      vector.set(currentIndex, (int) time.getTime());
      currentIndex++;
    }
  }
}