common/src/main/java/com/metamx/druid/aggregation/LongSumBufferAggregator.java

/*
 * Druid - a distributed column store.
 * Copyright (C) 2012  Metamarkets Group Inc.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

package com.metamx.druid.aggregation;

import com.metamx.druid.processing.FloatMetricSelector;

import java.nio.ByteBuffer;

/**
 */
public class LongSumBufferAggregator implements BufferAggregator
{
  private final FloatMetricSelector selector;

  public LongSumBufferAggregator(
      FloatMetricSelector selector
  )
  {
    this.selector = selector;
  }

  @Override
  public void init(ByteBuffer buf, int position)
  {
    buf.putLong(position, 0l);
  }

  @Override
  public void aggregate(ByteBuffer buf, int position)
  {
    buf.putLong(position, buf.getLong(position) + (long) selector.get());
  }

  @Override
  public Object get(ByteBuffer buf, int position)
  {
    return buf.getLong(position);
  }

  @Override
  public float getFloat(ByteBuffer buf, int position)
  {
    return (float) buf.getLong(position);
  }
}