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 package org.apache.commons.monitoring.web.session; 018 019 import org.apache.commons.monitoring.Role; 020 import org.apache.commons.monitoring.counters.Counter; 021 import org.apache.commons.monitoring.counters.Unit; 022 import org.apache.commons.monitoring.repositories.Repository; 023 import org.apache.commons.monitoring.stopwatches.StopWatch; 024 025 import javax.servlet.http.HttpSessionEvent; 026 import javax.servlet.http.HttpSessionListener; 027 import java.util.Map; 028 import java.util.concurrent.ConcurrentHashMap; 029 030 public class MonitoringSessionListener implements HttpSessionListener { 031 private final Map<String, StopWatch> watches = new ConcurrentHashMap<String, StopWatch>(); 032 033 private final Counter counter; 034 035 public MonitoringSessionListener() { 036 counter = Repository.INSTANCE.getCounter(new Counter.Key(new Role("session", Unit.UNARY), "session")); 037 } 038 039 @Override 040 public void sessionCreated(final HttpSessionEvent httpSessionEvent) { 041 final StopWatch watch = Repository.INSTANCE.start(counter); 042 watches.put(httpSessionEvent.getSession().getId(), watch); 043 } 044 045 @Override 046 public void sessionDestroyed(final HttpSessionEvent httpSessionEvent) { 047 final StopWatch watch = watches.remove(httpSessionEvent.getSession().getId()); 048 if (watch != null) { 049 watch.stop(); 050 } 051 } 052 }