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.malhar.contrib.enrich;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Map;
  
  import org.apache.apex.malhar.lib.util.FieldInfo;
  import org.apache.hadoop.classification.InterfaceStability;
  
  import com.datatorrent.api.DefaultInputPort;
  import com.datatorrent.api.DefaultOutputPort;
  
  /**
   * This class takes a HashMap tuple as input and extracts value of the lookupKey configured
   * for this operator. It perform a lookup using {@link org.apache.apex.malhar.lib.db.cache.CacheManager} to
   * find a matching entry and adds the result to the original tuple.
   *
   * <p>
   * Example:
   * Lets say, input tuple is
   *    { amount=10.0, channelId=4, productId=3 }
   * The tuple is modified as below:
   *    { amount=10.0, channelId=4, productId=3, <b>productCategory=1 </b>}
   * </p>
   *
   * @displayName MapEnricher
   * @category Database
   * @tags enrichment, lookup, map
   *
   * @since 3.4.0
   */
  @InterfaceStability.Evolving
  public class MapEnricher extends AbstractEnricher<Map<String, Object>, Map<String, Object>>
  {
    public final transient DefaultInputPort<Map<String, Object>> input = new DefaultInputPort<Map<String, Object>>()
    {
      @Override
      public void process(Map<String, Object> obj)
      {
        processTuple(obj);
      }
    };
  
    public final transient DefaultOutputPort<Map<String, Object>> output = new DefaultOutputPort<>();
  
    protected void processTuple(Map<String, Object> obj)
    {
      enrichTuple(obj);
    }
  
    @Override
    protected Object getKey(Map<String, Object> tuple)
    {
      ArrayList<Object> keyList = new ArrayList<Object>();
  
      for (FieldInfo fieldInfo : lookupFieldInfo) {
        keyList.add(tuple.get(fieldInfo.getColumnName()));
      }
  
      return keyList;
    }
  
    @Override
    protected Map<String, Object> convert(Map<String, Object> in, Object cached)
    {
      if (cached == null) {
        return in;
      }
  
      ArrayList<Object> newAttributes = (ArrayList<Object>)cached;
      if (newAttributes != null) {
        for (int i = 0; i < includeFieldInfo.size(); i++) {
          in.put(includeFieldInfo.get(i).getColumnName(), newAttributes.get(i));
        }
      }
      return in;
    }
  
    @Override
    protected void emitEnrichedTuple(Map<String, Object> tuple)
    {
      output.emit(tuple);
    }
  
    @Override
    protected Class<?> getIncludeFieldType(String fieldName)
    {
      return Object.class;
    }
  
    @Override
    protected Class<?> getLookupFieldType(String fieldName)
    {
      return Object.class;
    }
  
    /**
     * Set fields on which lookup against which lookup will be performed.
     * This is a mandatory parameter to set.
     *
     * @param lookupFields List of fields on which lookup happens.
     * @description $[] Field which become part of lookup key
     */
    @Override
    public void setLookupFields(List<String> lookupFields)
    {
      super.setLookupFields(lookupFields);
    }
  
    /**
     * Set fields which will enrich the map.
     * This is a mandatory parameter to set.
     *
     * @param includeFields List of fields.
     * @description $[] Field which are fetched from store
     */
    @Override
    public void setIncludeFields(List<String> includeFields)
    {
      super.setIncludeFields(includeFields);
    }
  }
  