extensions-core/druid-bloom-filter/src/main/java/org/apache/druid/query/aggregation/bloom/BloomFilterMergeAggregator.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.query.aggregation.bloom;

import org.apache.druid.java.util.common.ISE;
import org.apache.druid.query.filter.BloomKFilter;
import org.apache.druid.segment.BaseObjectColumnValueSelector;

import java.nio.ByteBuffer;

public final class BloomFilterMergeAggregator
    extends BaseBloomFilterAggregator<BaseObjectColumnValueSelector<ByteBuffer>>
{
  BloomFilterMergeAggregator(BaseObjectColumnValueSelector<ByteBuffer> selector, int maxNumEntries, boolean onHeap)
  {
    super(selector, maxNumEntries, onHeap);
  }

  @Override
  public void bufferAdd(ByteBuffer buf)
  {
    ByteBuffer other = selector.getObject();
    if (other == null) {
      // nulls should be empty bloom filters by this point, so encountering a nil column in merge agg is unexpected
      throw new ISE("Unexpected null value in BloomFilterMergeAggregator");
    }
    BloomKFilter.mergeBloomFilterByteBuffers(buf, buf.position(), other, other.position());
  }
}