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.activemq.web;
018    
019    import java.util.HashMap;
020    import java.util.Map;
021    import java.util.Date;
022    
023    import javax.jms.MessageConsumer;
024    import javax.servlet.http.HttpServletRequest;
025    
026    import org.slf4j.Logger;
027    import org.slf4j.LoggerFactory;
028    
029    import org.apache.activemq.MessageAvailableConsumer;
030    
031    /*
032     * Collection of all data needed to fulfill requests from a single web client.
033     */
034    public class AjaxWebClient extends WebClient {
035        private static final Logger LOG = LoggerFactory.getLogger(AjaxWebClient.class);
036        
037        // an instance which has not been accessed in this many milliseconds can be removed.
038        final long expireAfter = 60 * 1000;
039        
040        Map<MessageAvailableConsumer, String> idMap;
041        Map<MessageAvailableConsumer, String> destinationNameMap;
042        AjaxListener listener;
043        Long lastAccessed;
044        
045        public AjaxWebClient( HttpServletRequest request, long maximumReadTimeout ) {
046            // 'id' meaning the first argument to the JavaScript addListener() function.
047            // used to indicate which JS callback should handle a given message.
048            this.idMap = new HashMap<MessageAvailableConsumer, String>();
049            
050            // map consumers to destinations like topic://test, etc.
051            this.destinationNameMap = new HashMap<MessageAvailableConsumer, String>();
052            
053            this.listener = new AjaxListener( this, maximumReadTimeout );
054            
055            this.lastAccessed = this.getNow();
056        }
057        
058        public Map<MessageAvailableConsumer, String> getIdMap() {
059            return this.idMap;
060        }
061        
062        public Map<MessageAvailableConsumer, String> getDestinationNameMap() {
063            return this.destinationNameMap;
064        }
065        
066        public AjaxListener getListener() {
067            return this.listener;
068        }
069        
070        public long getMillisSinceLastAccessed() {
071            return this.getNow() - this.lastAccessed;
072        }
073        
074        public void updateLastAccessed() {
075            this.lastAccessed = this.getNow();
076        }
077        
078        public boolean closeIfExpired() {
079            long now = (new Date()).getTime();
080            boolean returnVal = false;
081            if( this.getMillisSinceLastAccessed() > this.expireAfter ) {
082                this.close();
083                returnVal = true;
084            }
085            return returnVal;
086        }
087        
088        protected long getNow() {
089            return (new Date()).getTime();
090        }
091    }