processing/src/main/java/org/apache/druid/segment/serde/LongNumericColumnPartSerdeV2.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.druid.segment.serde;

import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonProperty;
import org.apache.druid.collections.bitmap.ImmutableBitmap;
import org.apache.druid.common.config.NullHandling;
import org.apache.druid.java.util.common.io.smoosh.FileSmoosher;
import org.apache.druid.segment.column.ValueType;
import org.apache.druid.segment.data.BitmapSerde;
import org.apache.druid.segment.data.BitmapSerdeFactory;
import org.apache.druid.segment.data.CompressedColumnarLongsSupplier;

import javax.annotation.Nullable;
import java.io.IOException;
import java.nio.ByteOrder;
import java.nio.channels.WritableByteChannel;

/**
 */
public class LongNumericColumnPartSerdeV2 implements ColumnPartSerde
{
  @JsonCreator
  public static LongNumericColumnPartSerdeV2 createDeserializer(
      @JsonProperty("byteOrder") ByteOrder byteOrder,
      @JsonProperty("bitmapSerdeFactory") @Nullable BitmapSerdeFactory bitmapSerdeFactory
  )
  {
    return new LongNumericColumnPartSerdeV2(
        byteOrder,
        bitmapSerdeFactory != null ? bitmapSerdeFactory : new BitmapSerde.LegacyBitmapSerdeFactory(),
        null
    );
  }

  @Nullable
  private final Serializer serializer;
  @Nullable
  private final ByteOrder byteOrder;
  @Nullable
  private final BitmapSerdeFactory bitmapSerdeFactory;

  private LongNumericColumnPartSerdeV2(
      @Nullable ByteOrder byteOrder,
      @Nullable BitmapSerdeFactory bitmapSerdeFactory,
      @Nullable Serializer serializer
  )
  {
    this.byteOrder = byteOrder;
    this.bitmapSerdeFactory = bitmapSerdeFactory;
    this.serializer = serializer;
  }

  @JsonProperty
  public ByteOrder getByteOrder()
  {
    return byteOrder;
  }

  @JsonProperty
  public BitmapSerdeFactory getBitmapSerdeFactory()
  {
    return bitmapSerdeFactory;
  }

  public static SerializerBuilder serializerBuilder()
  {
    return new SerializerBuilder();
  }

  public static class SerializerBuilder
  {
    @Nullable
    private ByteOrder byteOrder = null;
    @Nullable
    private Serializer delegate = null;
    @Nullable
    private BitmapSerdeFactory bitmapSerdeFactory = null;

    public SerializerBuilder withByteOrder(final ByteOrder byteOrder)
    {
      this.byteOrder = byteOrder;
      return this;
    }

    public SerializerBuilder withDelegate(final Serializer delegate)
    {
      this.delegate = delegate;
      return this;
    }

    public SerializerBuilder withBitmapSerdeFactory(BitmapSerdeFactory bitmapSerdeFactory)
    {
      this.bitmapSerdeFactory = bitmapSerdeFactory;
      return this;
    }

    public LongNumericColumnPartSerdeV2 build()
    {
      Serializer serializer = new Serializer()
      {
        @Override
        public long getSerializedSize() throws IOException
        {
          return delegate.getSerializedSize();
        }

        @Override
        public void writeTo(WritableByteChannel channel, FileSmoosher smoosher) throws IOException
        {
          delegate.writeTo(channel, smoosher);
        }
      };
      return new LongNumericColumnPartSerdeV2(byteOrder, bitmapSerdeFactory, serializer);
    }
  }

  @Nullable
  @Override
  public Serializer getSerializer()
  {
    return serializer;
  }

  @Override
  public Deserializer getDeserializer()
  {
    return (buffer, builder, columnConfig) -> {
      int offset = buffer.getInt();
      int initialPos = buffer.position();
      final CompressedColumnarLongsSupplier column = CompressedColumnarLongsSupplier.fromByteBuffer(
          buffer,
          byteOrder
      );
      buffer.position(initialPos + offset);
      final ImmutableBitmap bitmap;
      final boolean hasNulls;
      if (buffer.hasRemaining() && NullHandling.sqlCompatible()) {
        if (NullHandling.sqlCompatible()) {
          bitmap = bitmapSerdeFactory.getObjectStrategy().fromByteBufferWithSize(buffer);
        } else {
          // Read from the buffer (to advance its position) but do not actually retain the bitmaps.
          bitmapSerdeFactory.getObjectStrategy().fromByteBufferWithSize(buffer);
          bitmap = bitmapSerdeFactory.getBitmapFactory().makeEmptyImmutableBitmap();
        }

        hasNulls = !bitmap.isEmpty();
      } else {
        bitmap = bitmapSerdeFactory.getBitmapFactory().makeEmptyImmutableBitmap();
        hasNulls = false;
      }
      builder.setType(ValueType.LONG)
             .setHasMultipleValues(false)
             .setHasNulls(hasNulls)
             .setNumericColumnSupplier(new LongNumericColumnSupplier(column, bitmap))
             .setNullValueIndexSupplier(bitmap);
    };
  }
}