001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *     http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    
018    package org.apache.commons.pipeline.listener;
019    
020    import java.util.Collections;
021    import java.util.EventObject;
022    import java.util.HashMap;
023    import java.util.Map;
024    
025    import org.apache.commons.pipeline.Stage;
026    import org.apache.commons.pipeline.StageEventListener;
027    import org.apache.commons.pipeline.event.ObjectProcessedEvent;
028    
029    /**
030     * This listener keeps track of the number of {@link ObjectProcessedEvent}s
031     * received from each {@link Stage}
032     *
033     *
034     */
035    public class ObjectProcessedEventCounter implements StageEventListener {
036        //private final Log log = LogFactory.getLog(ObjectProcessedEventCounter.class);
037        
038        private Map<Stage,Integer> counts = Collections.synchronizedMap(new HashMap<Stage, Integer>());
039        
040        public synchronized void notify(EventObject evo) {
041            if (evo instanceof ObjectProcessedEvent) {
042            ObjectProcessedEvent ev = (ObjectProcessedEvent) evo;
043            if (!counts.containsKey(ev.getSource())) counts.put(ev.getSource(), 1);
044        }
045        }
046        
047        public synchronized Map<Stage, Integer> getCounts() {
048            return this.counts;
049        }
050    }