/**

  * Copyright 2005-2011 The Kuali Foundation

  *

  * Licensed under the Educational Community License, Version 2.0 (the "License");

  * you may not use this file except in compliance with the License.

  * You may obtain a copy of the License at

  *

  * http://www.opensource.org/licenses/ecl2.php

  *

  * Unless required by applicable law or agreed to in writing, software

  * distributed under the License is distributed on an "AS IS" BASIS,

  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

  * See the License for the specific language governing permissions and

  * limitations under the License.

  */

 package org.kuali.rice.ken.core;

 import org.apache.log4j.Logger;

 import org.springframework.beans.factory.BeanFactory;

 /**

  * Class that holds a singleton reference to NotificationServiceLocator

  * @author Kuali Rice Team (rice.collab@kuali.org)

  */

 public class GlobalNotificationServiceLocator {

     private static final Logger LOG = Logger.getLogger(GlobalNotificationServiceLocator.class);

     /**

      * The NotificationServiceLocator singleton

      */

     private static NotificationServiceLocator locator;

     /**

      * The global initializer that constructs the NotificationServiceLocator singleton

      * @param beanFactory the beanFactory from which to construct the SpringNotificationServiceLocator

      */

     public static synchronized void init(BeanFactory beanFactory) {

         //LOG.debug("INITIALIZING", new Exception());

         if (locator != null) {

             throw new IllegalStateException("GlobalNotificationServiceLocator already initialized");

         }

         locator = new SpringNotificationServiceLocator(beanFactory);

     }

     /**

      * Returns whether the GlobalNotificationServiceLocator has already been initialized (classloader scoped)

      * @return whether the GlobalNotificationServiceLocator has already been initialized (classloader scoped)

      */

     public static synchronized boolean isInitialized() {

         return locator != null;

     }

     /**

      * Un-sets the NotificationServiceLocator singleton, in order to fulfill a "lifecycle"

      * contract (whereby init may be called again in the same class loader), specifically for

      * unit tests. 

      */

     public static synchronized void destroy() {

         //LOG.debug("DESTROYING", new Exception());

         locator = null;

     }

     /**

      * Return the NotificationServiceLocator singleton

      * @return the NotificationServiceLocator singleton

      */

     public static NotificationServiceLocator getInstance() {

         return locator;

     }

 }