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.misc.algo;
  
  import java.util.HashMap;
  import java.util.Map;
  
  import javax.validation.constraints.NotNull;
  
  import org.apache.apex.malhar.lib.util.BaseKeyOperator;
  
  import com.datatorrent.api.DefaultInputPort;
  import com.datatorrent.api.DefaultOutputPort;
  import com.datatorrent.api.annotation.OperatorAnnotation;
  import com.datatorrent.api.annotation.Stateless;
  
  /**
   * This operator filters the incoming stream of tuples using a set of specified key value pairs.&nbsp;
   * Tuples that match the filter are emitted by the operator.
   * <p>
   * Filters the incoming stream based of specified key,val pairs, and emits those that match the filter. If
   * property "inverse" is set to "true", then all key,val pairs except those specified by in keyvals parameter are emitted
   * </p>
   * <p>
   * Operator assumes that the key, val pairs are immutable objects. If this operator has to be used for mutable objects,
   * override "cloneKey()" to make copy of K, and "cloneValue()" to make copy of V.<br>
   * This is a pass through node<br>
   * <br>
   * <b>StateFull : No, </b> tuple are processed in current window. <br>
   * <b>Partitions : Yes, </b> no dependency among input tuples. <br>
   * <br>
   * <b>Ports</b>:<br>
   * <b>data</b>: expects HashMap&lt;K,V&gt;<br>
   * <b>filter</b>: emits HashMap&lt;K,V&gt;(1)<br>
   * <br>
   * <b>Properties</b>:<br>
   * <b>keyvals</b>: The keyvals is key,val pairs to pass through, rest are filtered/dropped.<br>
   * <br>
   * </p>
   *
   * @displayName Filter Keyval Pairs
   * @category Rules and Alerts
   * @tags filter, key value
   *
   * @since 0.3.2
   * @deprecated
   */
  @Deprecated
  @Stateless
  @OperatorAnnotation(partitionable = true)
  public class FilterKeyVals<K,V> extends BaseKeyOperator<K>
  {
    /**
     * The input port on which key value pairs are received.
     */
    public final transient DefaultInputPort<HashMap<K, V>> data = new DefaultInputPort<HashMap<K, V>>()
    {
      /**
       * Processes incoming tuples one key,val at a time. Emits if at least one key makes the cut
       * By setting inverse as true, match is changed to un-matched
       */
      @Override
      public void process(HashMap<K, V> tuple)
      {
        for (Map.Entry<K, V> e: tuple.entrySet()) {
          entry.clear();
          entry.put(e.getKey(),e.getValue());
          boolean contains = keyvals.containsKey(entry);
          if ((contains && !inverse) || (!contains && inverse)) {
            HashMap<K, V> dtuple = new HashMap<K,V>(1);
            dtuple.put(cloneKey(e.getKey()), cloneValue(e.getValue()));
            filter.emit(dtuple);
          }
        }
      }
    };
  
    /**
     * The output port on which filtered key value pairs are emitted.
     */
    public final transient DefaultOutputPort<HashMap<K, V>> filter = new DefaultOutputPort<HashMap<K, V>>();
  
    @NotNull()
    HashMap<HashMap<K,V>,Object> keyvals = new HashMap<HashMap<K,V>,Object>();
    boolean inverse = false;
    private transient HashMap<K,V> entry = new HashMap<K,V>(1);
  
    /**
     * Gets the inverse property.
     * @return inverse
     */
    public boolean getInverse()
    {
      return inverse;
    }
  
    /**
     * If true then only matches are emitted. If false then only non matches are emitted.
     * @param val
     */
    public void setInverse(boolean val)
    {
      inverse = val;
    }
  
    /**
     * True means match; False means unmatched
     * @return keyvals hash
     */
    @NotNull()
    public HashMap<HashMap<K,V>,Object> getKeyVals()
    {
      return keyvals;
    }
  
    /**
     * Adds a key to the filter list
     * @param map with key,val pairs to set as filters
     */
    @SuppressWarnings({ "unchecked", "rawtypes" })
    public void setKeyVals(HashMap<K,V> map)
    {
      for (Map.Entry<K, V> e: map.entrySet()) {
        HashMap kvpair = new HashMap<K,V>(1);
        kvpair.put(cloneKey(e.getKey()), cloneValue(e.getValue()));
        keyvals.put(kvpair, null);
      }
    }
  
    /*
     * Clears the filter list
     */
    public void clearKeys()
    {
      keyvals.clear();
    }
  
    /**
     * Clones V object. By default assumes immutable object (i.e. a copy is not made). If object is mutable, override this method
     * @param v value to be cloned
     * @return returns v as is (assumes immutable object)
     */
    public V cloneValue(V v)
    {
      return v;
    }
  }
  