modules/gemfire-modules/src/main/java/com/gemstone/gemfire/modules/session/catalina/callback/SessionExpirationCacheListener.java

/*=========================================================================
 * Copyright (c) 2010-2014 Pivotal Software, Inc. All Rights Reserved.
 * This product is protected by U.S. and international copyright
 * and intellectual property laws. Pivotal products are covered by
 * one or more patents listed at http://www.pivotal.io/patents.
 *=========================================================================
 */
package com.gemstone.gemfire.modules.session.catalina.callback;

import com.gemstone.gemfire.cache.Declarable;
import com.gemstone.gemfire.cache.EntryEvent;
import com.gemstone.gemfire.cache.Operation;

import com.gemstone.gemfire.cache.util.CacheListenerAdapter;
import com.gemstone.gemfire.modules.session.catalina.DeltaSession;
import com.gemstone.gemfire.modules.session.catalina.DeltaSessionManager;
import com.gemstone.gemfire.modules.util.ContextMapper;

import java.util.Properties;

import javax.servlet.http.HttpSession;

public class SessionExpirationCacheListener extends CacheListenerAdapter<String,HttpSession> implements Declarable {

  public void afterDestroy(EntryEvent<String,HttpSession> event) {
    // A Session expired. If it was destroyed by GemFire expiration, process it.
    // If it was destroyed via Session.invalidate, ignore it since it has
    // already been processed.
    DeltaSession session = null;
    if (event.getOperation() == Operation.EXPIRE_DESTROY) {
      session = (DeltaSession) event.getOldValue();
    } else {
      /*
       * This comes into play when we're dealing with an empty client proxy. We
       * need the actual destroyed object to come back from the server so that
       * any associated listeners can fire correctly. Having the destroyed
       * object come back as the callback arg depends on setting the property
       * gemfire.EXPIRE_SENDS_ENTRY_AS_CALLBACK.
       */
      Object callback = event.getCallbackArgument();
      if (callback != null && callback instanceof DeltaSession) {
        session = (DeltaSession) callback;
        DeltaSessionManager m = ContextMapper.getContext(
            session.getContextName());
        if (m != null) {
          session.setOwner(m);
        }
      }
    }
    if (session != null) {
      session.processExpired();
    }
  }

  public void init(Properties p) {}

  public boolean equals(Object obj) {
    // This method is only implemented so that RegionAttributesCreation.sameAs
    // works properly.
    if (this == obj) {
      return true;
    }

    if (obj == null || !(obj instanceof SessionExpirationCacheListener)) {
      return false;
    }

    return true;
  }
}