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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *     http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17  
18  package org.apache.commons.pipeline.listener;
19  
20  import java.util.Collections;
21  import java.util.EventObject;
22  import java.util.HashMap;
23  import java.util.Map;
24  
25  import org.apache.commons.pipeline.Stage;
26  import org.apache.commons.pipeline.StageEventListener;
27  import org.apache.commons.pipeline.event.ObjectProcessedEvent;
28  
29  /**
30   * This listener keeps track of the number of {@link ObjectProcessedEvent}s
31   * received from each {@link Stage}
32   *
33   *
34   */
35  public class ObjectProcessedEventCounter implements StageEventListener {
36      //private final Log log = LogFactory.getLog(ObjectProcessedEventCounter.class);
37      
38      private Map<Stage,Integer> counts = Collections.synchronizedMap(new HashMap<Stage, Integer>());
39      
40      public synchronized void notify(EventObject evo) {
41          if (evo instanceof ObjectProcessedEvent) {
42          ObjectProcessedEvent ev = (ObjectProcessedEvent) evo;
43          if (!counts.containsKey(ev.getSource())) counts.put(ev.getSource(), 1);
44      }
45      }
46      
47      public synchronized Map<Stage, Integer> getCounts() {
48          return this.counts;
49      }
50  }