demos/src/main/java/com/datatorrent/demos/machinedata/operator/MachineInfoAveragingPrerequisitesOperator.java

/*
 * Copyright (c) 2013 DataTorrent, Inc. ALL Rights Reserved.
 *
 * Licensed 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 com.datatorrent.demos.machinedata.operator;

import com.datatorrent.api.BaseOperator;
import com.datatorrent.api.DefaultInputPort;
import com.datatorrent.api.DefaultOutputPort;
import com.datatorrent.demos.machinedata.data.MachineKey;
import com.datatorrent.demos.machinedata.data.MachineInfo;
import com.datatorrent.demos.machinedata.data.AverageData;
import com.datatorrent.lib.util.KeyHashValPair;

import org.apache.commons.lang.mutable.MutableDouble;
import org.apache.commons.lang.mutable.MutableLong;

import java.util.HashMap;
import java.util.Map;

/**
 * This class calculates the partial sum and count for tuples generated by upstream Operator
 * <p> MachineInfoAveragingPrerequisitesOperator class. </p>
 *
 * @since 0.3.5
 */
public class MachineInfoAveragingPrerequisitesOperator extends BaseOperator
{

  // Aggregate sum of all values seen for a key.
  private Map<MachineKey, Map<String, MutableDouble>> sums = new HashMap<MachineKey, Map<String, MutableDouble>>();

  // Count of number of values seen for key.
  private Map<MachineKey, MutableLong> counts = new HashMap<MachineKey, MutableLong>();

  public final transient DefaultOutputPort<KeyHashValPair<MachineKey, Map<String, AverageData>>> outputPort = new DefaultOutputPort<KeyHashValPair<MachineKey, Map<String, AverageData>>>(){
    public Unifier<KeyHashValPair<MachineKey,Map<String,AverageData>>> getUnifier() {
      MachineInfoAveragingUnifier unifier = new MachineInfoAveragingUnifier();
      return unifier;
    };
  };

  public transient DefaultInputPort<MachineInfo> inputPort = new DefaultInputPort<MachineInfo>() {

    @Override
    public void process(MachineInfo tuple)
    {
      MachineKey key = tuple.getMachineKey();

      Map<String, MutableDouble> sumsMap = sums.get(key);
      if (sumsMap == null) {
        sumsMap = new HashMap<String, MutableDouble>();
        sumsMap.put("cpu", new MutableDouble(tuple.getCpu()));
        sumsMap.put("ram", new MutableDouble(tuple.getRam()));
        sumsMap.put("hdd", new MutableDouble(tuple.getHdd()));
        sums.put(key, sumsMap);
      } else {
        sumsMap.get("cpu").add(tuple.getCpu());
        sumsMap.get("ram").add(tuple.getRam());
        sumsMap.get("hdd").add(tuple.getHdd());
      }

      MutableLong count = counts.get(key);
      if (count == null) {
        count = new MutableLong(1);
        counts.put(key, count);
      } else {
        count.increment();
      }
    }
  };

  @Override
  public void endWindow()
  {

    for (Map.Entry<MachineKey, Map<String, MutableDouble>> entry : sums.entrySet()) {

      Map<String, MutableDouble> sumMap = entry.getValue();
      long count = counts.get(entry.getKey()).longValue();

      Map<String, AverageData> avg = new HashMap<String, AverageData>();
      avg.put("cpu", new AverageData(sumMap.get("cpu").doubleValue(), count));
      avg.put("ram", new AverageData(sumMap.get("ram").doubleValue(), count));
      avg.put("hdd", new AverageData(sumMap.get("hdd").doubleValue(), count));

      if (outputPort.isConnected()) {
        outputPort.emit(new KeyHashValPair<MachineKey, Map<String, AverageData>>(entry.getKey(), avg));
      }
    }
    sums.clear();
    counts.clear();
  }

}