server/runtime/org.argeo.server.jcr/src/main/java/org/argeo/jcr/DefaultJcrListener.java

   1 /*
   2  * Copyright (C) 2010 Mathieu Baudier <mbaudier@argeo.org>
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *         http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 package org.argeo.jcr;
  18
  19 import javax.jcr.RepositoryException;
  20 import javax.jcr.Session;
  21 import javax.jcr.observation.Event;
  22 import javax.jcr.observation.EventIterator;
  23 import javax.jcr.observation.EventListener;
  24 import javax.jcr.observation.ObservationManager;
  25
  26 import org.apache.commons.logging.Log;
  27 import org.apache.commons.logging.LogFactory;
  28 import org.argeo.ArgeoException;
  29
  30 /** To be overridden */
  31 public class DefaultJcrListener implements EventListener {
  32         private final static Log log = LogFactory.getLog(DefaultJcrListener.class);
  33         private Session session;
  34         private String path = "/";
  35         private Boolean deep = true;
  36
  37         public void start() {
  38                 try {
  39                         addEventListener(session().getWorkspace().getObservationManager());
  40                         if (log.isDebugEnabled())
  41                                 log.debug("Registered JCR event listener on " + path);
  42                 } catch (Exception e) {
  43                         throw new ArgeoException("Cannot register event listener", e);
  44                 }
  45         }
  46
  47         public void stop() {
  48                 try {
  49                         session().getWorkspace().getObservationManager()
  50                                         .removeEventListener(this);
  51                         if (log.isDebugEnabled())
  52                                 log.debug("Unregistered JCR event listener on " + path);
  53                 } catch (Exception e) {
  54                         throw new ArgeoException("Cannot unregister event listener", e);
  55                 }
  56         }
  57
  58         /** Default is listen to all events */
  59         protected Integer getEvents() {
  60                 return Event.NODE_ADDED | Event.NODE_REMOVED | Event.PROPERTY_ADDED
  61                                 | Event.PROPERTY_CHANGED | Event.PROPERTY_REMOVED;
  62         }
  63
  64         /** To be overidden */
  65         public void onEvent(EventIterator events) {
  66                 while (events.hasNext()) {
  67                         Event event = events.nextEvent();
  68                         log.debug(event);
  69                 }
  70         }
  71
  72         /** To be overidden */
  73         protected void addEventListener(ObservationManager observationManager)
  74                         throws RepositoryException {
  75                 observationManager.addEventListener(this, getEvents(), path, deep,
  76                                 null, null, false);
  77         }
  78
  79         private Session session() {
  80                 return session;
  81         }
  82
  83         public void setPath(String path) {
  84                 this.path = path;
  85         }
  86
  87         public void setDeep(Boolean deep) {
  88                 this.deep = deep;
  89         }
  90
  91         public void setSession(Session session) {
  92                 this.session = session;
  93         }
  94
  95 }