View Javadoc

    1   /* Copyright 2004, 2005 Acegi Technology Pty Limited
    2    *
    3    * Licensed under the Apache License, Version 2.0 (the "License");
    4    * you may not use this file except in compliance with the License.
    5    * You may obtain a copy of the License at
    6    *
    7    *     http://www.apache.org/licenses/LICENSE-2.0
    8    *
    9    * Unless required by applicable law or agreed to in writing, software
    10   * distributed under the License is distributed on an "AS IS" BASIS,
    11   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12   * See the License for the specific language governing permissions and
    13   * limitations under the License.
    14   */
    15
    16  package org.acegisecurity.ui.session;
    17
    18  import org.apache.commons.logging.Log;
    19  import org.apache.commons.logging.LogFactory;
    20
    21  import org.springframework.context.ApplicationContext;
    22
    23  import org.springframework.web.context.support.WebApplicationContextUtils;
    24  import org.springframework.util.Assert;
    25
    26  import javax.servlet.ServletContextEvent;
    27  import javax.servlet.ServletContextListener;
    28  import javax.servlet.http.HttpSessionEvent;
    29  import javax.servlet.http.HttpSessionListener;
    30
    31
    32  /***
    33   * Declared in web.xml as <br>
    34   * <code> &lt;listener&gt;<br>
    35   * &lt;listener-class&gt;org.acegisecurity.ui.session.HttpSessionEventPublisher&lt;/listener-class&gt;<br>
    36   * &lt;/listener&gt;<br>
    37   * </code> Publishes <code>HttpSessionApplicationEvent</code>s to the Spring
    38   * Root WebApplicationContext. <br>
    39   * Maps javax.servlet.http.HttpSessionListener.sessionCreated() to {@link
    40   * HttpSessionCreatedEvent}. <br>
    41   * Maps javax.servlet.http.HttpSessionListener.sessionDestroyed() to {@link
    42   * HttpSessionDestroyedEvent}. <br>
    43   *
    44   * @author Ray Krueger
    45   */
    46  public class HttpSessionEventPublisher implements HttpSessionListener,
    47      ServletContextListener {
    48      //~ Static fields/initializers =============================================
    49
    50      private static final Log log = LogFactory.getLog(HttpSessionEventPublisher.class);
    51
    52      //~ Instance fields ========================================================
    53
    54      private ApplicationContext context;
    55
    56      //~ Methods ================================================================
    57
    58      /***
    59       * Not implemented
    60       *
    61       * @param event
    62       */
    63      public void contextDestroyed(ServletContextEvent event) {}
    64
    65      /***
    66       * Handled internally by a call to {@link
    67       * org.springframework.web.context.support.WebApplicationContextUtils#getRequiredWebApplicationContext(javax.servlet.ServletContext)}
    68       *
    69       * @param event the ServletContextEvent passed in by the container,
    70       *        event.getServletContext() will be used to get the
    71       *        WebApplicationContext
    72       */
    73      public void contextInitialized(ServletContextEvent event) {
    74          if (log.isDebugEnabled())
    75              log.debug("Received ServletContextEvent: " + event);
    76          setContext(WebApplicationContextUtils.getRequiredWebApplicationContext(
    77                  event.getServletContext()));
    78      }
    79
    80      /***
    81       * Handles the HttpSessionEvent by publishing a {@link
    82       * HttpSessionCreatedEvent} to the application context.
    83       *
    84       * @param event HttpSessionEvent passed in by the container
    85       */
    86      public void sessionCreated(HttpSessionEvent event) {
    87          HttpSessionCreatedEvent e = new HttpSessionCreatedEvent(event
    88                  .getSession());
    89
    90          log.debug("Publishing event: " + e);
    91
    92          getContext().publishEvent(e);
    93      }
    94
    95      /***
    96       * Handles the HttpSessionEvent by publishing a {@link
    97       * HttpSessionDestroyedEvent} to the application context.
    98       *
    99       * @param event The HttpSessionEvent pass in by the container
    100      */
    101     public void sessionDestroyed(HttpSessionEvent event) {
    102         HttpSessionDestroyedEvent e = new HttpSessionDestroyedEvent(event
    103                 .getSession());
    104
    105         log.debug("Publishing event: " + e);
    106
    107         getContext().publishEvent(e);
    108     }
    109
    110     /***
    111      * Package level method for testing and internal usage
    112      *
    113      * @param context The ApplicationContext this class will use to publish
    114      *        events
    115      */
    116     void setContext(ApplicationContext context) {
    117         this.context = context;
    118         log.debug("Using context: " + context);
    119     }
    120
    121     ApplicationContext getContext() {
    122        Assert.notNull(context, "setContext(...) never called, ApplicationContext must not be null");
    123         return context;
    124     }
    125 }