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 org.apache.apex.malhar.lib.util.BaseMatchOperator;
  
  import com.datatorrent.api.DefaultInputPort;
  import com.datatorrent.api.DefaultOutputPort;
  import com.datatorrent.api.annotation.OperatorAnnotation;
  
  /**
   * This operator filters the incoming stream of key value pairs by obtaining the values corresponding to a specified key,
   * and comparing those values to a specified number.&nbsp;The first key value pair, in each window, to satisfy the comparison is emitted.
   * <p>
   * A compare metric on a Number tuple based on the property "key", "value", and "cmp"; the first match is emitted.
   *  The comparison is done by getting double value from the Number.
   * </p>
   * <p>
   * This module is a pass through<br>
   * The operators by default assumes immutable keys. If the key is mutable, use cloneKey to make a copy<br>
   * <br>
   * <b>StateFull : Yes, </b> tuple are processed in current window. <br>
   * <b>Partitions : No, </b>will yield wrong results. <br>
   * <br>
   * <br>
   * <b>Ports</b>:<br>
   * <b>data</b>: expects Map&lt;K,V extends Number&gt;<br>
   * <b>first</b>: emits HashMap&lt;K,V&gt;<br>
   * <br>
   * <b>Properties</b>:<br>
   * <b>key</b>: The key on which compare is done<br>
   * <b>value</b>: The value to compare with<br>
   * <b>cmp</b>: The compare function. Supported values are "lte", "lt", "eq", "neq", "gt", "gte". Default is "eq"<br>
   * <br>
   * <b>Specific compile time checks</b>:<br>
   * Key must be non empty<br>
   * Value must be able to convert to a "double"<br>
   * Compare string, if specified, must be one of "lte", "lt", "eq", "neq", "gt", "gte"<br>
   * <br>
   * </p>
   *
   * @displayName Emit First Match (Number)
   * @category Rules and Alerts
   * @tags filter, key value, numeric
   *
   * @since 0.3.2
   * @deprecated
   */
  @Deprecated
  @OperatorAnnotation(partitionable = false)
  public class FirstMatchMap<K, V extends Number> extends BaseMatchOperator<K,V>
  {
    /**
     * Tuple emitted flag.
     */
    boolean emitted = false;
  
    /**
     * The port on which key value pairs are received.
     */
    public final transient DefaultInputPort<Map<K, V>> data = new DefaultInputPort<Map<K, V>>()
    {
      /**
       * Checks if required key,val pair exists in the HashMap. If so tuple is emitted, and emitted flag is set
       * to true
       */
      @Override
      public void process(Map<K, V> tuple)
      {
        if (emitted) {
          return;
        }
        V val = tuple.get(getKey());
        if (val == null) { // skip if key does not exist
          return;
        }
        if (compareValue(val.doubleValue())) {
          first.emit(cloneTuple(tuple));
          emitted = true;
        }
      }
    };
  
    /**
     * The output port on which the first satisfying key value pair is emitted.
     */
    public final transient DefaultOutputPort<HashMap<K, V>> first = new DefaultOutputPort<HashMap<K, V>>();
  
    /**
     * Resets emitted flag to false
     * @param windowId
     */
    @Override
    public void beginWindow(long windowId)
    {
      emitted = false;
    }
  }
  