content: /**
   * 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.apex.examples.frauddetect;
  
  import java.io.IOException;
  import java.util.HashMap;
  import java.util.Map;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.apache.apex.examples.frauddetect.util.JsonUtils;
  import org.apache.apex.malhar.lib.util.HighLow;
  import org.apache.apex.malhar.lib.util.KeyValPair;
  
  import com.datatorrent.api.DefaultInputPort;
  import com.datatorrent.api.DefaultOutputPort;
  import com.datatorrent.common.util.BaseOperator;
  
  /**
   * Operator to aggregate the min, max, sma, std-dev and variance for the given key.
   *
   * @since 0.9.0
   */
  public class TransactionStatsAggregator extends BaseOperator
  {
    public Map<MerchantKey, TransactionStatsData> aggrgateMap =
        new HashMap<MerchantKey, TransactionStatsData>();
    public final transient DefaultOutputPort<String> txDataOutputPort = new DefaultOutputPort<String>();
    public final transient DefaultInputPort<KeyValPair<MerchantKey, HighLow<Long>>> rangeInputPort =
        new DefaultInputPort<KeyValPair<MerchantKey, HighLow<Long>>>()
    {
      @Override
      public void process(KeyValPair<MerchantKey, HighLow<Long>> tuple)
      {
        TransactionStatsData data = getDataObjectFromMap(tuple.getKey());
        // HighLow is not currently typed, casting till it is fixed
        data.min = tuple.getValue().getLow();
        data.max = tuple.getValue().getHigh();
      }
  
    };
    public final transient DefaultInputPort<KeyValPair<MerchantKey, Long>> smaInputPort =
        new DefaultInputPort<KeyValPair<MerchantKey, Long>>()
    {
      @Override
      public void process(KeyValPair<MerchantKey, Long> tuple)
      {
        TransactionStatsData data = getDataObjectFromMap(tuple.getKey());
        data.sma = tuple.getValue();
      }
  
    };
  
    private TransactionStatsData getDataObjectFromMap(MerchantKey key)
    {
      TransactionStatsData data = aggrgateMap.get(key);
      if (data == null) {
        data = new TransactionStatsData();
        data.time = System.currentTimeMillis();
        data.merchantId = key.merchantId;
        data.terminalId = key.terminalId == null ? 0 : key.terminalId;
        data.zipCode = key.zipCode;
        data.merchantType = key.merchantType;
        aggrgateMap.put(key, data);
      }
      return data;
    }
  
    @Override
    public void endWindow()
    {
      for (Map.Entry<MerchantKey, TransactionStatsData> entry : aggrgateMap.entrySet()) {
        try {
          txDataOutputPort.emit(JsonUtils.toJson(entry.getValue()));
        } catch (IOException e) {
          logger.warn("Exception while converting object to JSON", e);
        }
      }
      aggrgateMap.clear();
    }
  
    private static final Logger logger = LoggerFactory.getLogger(TransactionStatsAggregator.class);
  }
  