/*

  * Licensed to the Apache Software Foundation (ASF) under one

  * or more contributor license agreements.  See the NOTICE file

  * distributed with this work for additional information

  * regarding copyright ownership.  The ASF licenses this file

  * to you under the Apache 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.apache.org/licenses/LICENSE-2.0

  *

  * 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.apache.shiro.spring;

 import org.springframework.beans.BeansException;

 import org.springframework.beans.FatalBeanException;

 import org.springframework.beans.factory.config.DestructionAwareBeanPostProcessor;

 import org.springframework.core.PriorityOrdered;

 import org.slf4j.Logger;

 import org.slf4j.LoggerFactory;

 import org.apache.shiro.util.Destroyable;

 import org.apache.shiro.util.Initializable;

 /**

  * <p>Bean post processor for Spring that automatically calls the <tt>init()</tt> and/or

  * <tt>destroy()</tt> methods on Shiro objects that implement the {@link org.apache.shiro.util.Initializable}

  * or {@link org.apache.shiro.util.Destroyable} interfaces, respectfully.  This post processor makes it easier

  * to configure Shiro beans in Spring, since the user never has to worry about whether or not if they

  * have to specify init-method and destroy-method bean attributes.</p>

  *

  * <p><b>Warning: This post processor has no way to determine if <tt>init()</tt> or <tt>destroy()</tt> have

  * already been called, so if you define this post processor in your applicationContext, do not also call these

  * methods manually or via Spring's <tt>init-method</tt> or <tt>destroy-method</tt> bean attributes.</b></p>

  *

  * @since 0.2

  */

 public class LifecycleBeanPostProcessor implements DestructionAwareBeanPostProcessor, PriorityOrdered {

     /**

      * Private internal class log instance.

      */

     private static final Logger log = LoggerFactory.getLogger(LifecycleBeanPostProcessor.class);

     /**

      * Order value of this BeanPostProcessor.

      */

     private int order;

     /**

      * Default Constructor.

      */

     public LifecycleBeanPostProcessor() {

         this(LOWEST_PRECEDENCE);

     }

     /**

      * Constructor with definable {@link #getOrder() order value}.

      *

      * @param order order value of this BeanPostProcessor.

      */

     public LifecycleBeanPostProcessor(int order) {

         this.order = order;

     }

     /**

      * Calls the <tt>init()</tt> methods on the bean if it implements {@link org.apache.shiro.util.Initializable}

      *

      * @param object the object being initialized.

      * @param name   the name of the bean being initialized.

      * @return the initialized bean.

      * @throws BeansException if any exception is thrown during initialization.

      */

     public Object postProcessBeforeInitialization(Object object, String name) throws BeansException {

         if (object instanceof Initializable) {

             try {

                 if (log.isDebugEnabled()) {

                     log.debug("Initializing bean [" + name + "]...");

                 }

                 ((Initializable) object).init();

             } catch (Exception e) {

                 throw new FatalBeanException("Error initializing bean [" + name + "]", e);

             }

         }

         return object;

     }

     /**

      * Does nothing - merely returns the object argument immediately.

      */

     public Object postProcessAfterInitialization(Object object, String name) throws BeansException {

         // Does nothing after initialization

         return object;

     }

     /**

      * Calls the <tt>destroy()</tt> methods on the bean if it implements {@link org.apache.shiro.util.Destroyable}

      *

      * @param object the object being initialized.

      * @param name   the name of the bean being initialized.

      * @throws BeansException if any exception is thrown during initialization.

      */

     public void postProcessBeforeDestruction(Object object, String name) throws BeansException {

         if (object instanceof Destroyable) {

             try {

                 if (log.isDebugEnabled()) {

                     log.debug("Destroying bean [" + name + "]...");

                 }

                 ((Destroyable) object).destroy();

             } catch (Exception e) {

                 throw new FatalBeanException("Error destroying bean [" + name + "]", e);

             }

         }

     }

     /**

      * Order value of this BeanPostProcessor.

      *

      * @return order value.

      */

     public int getOrder() {

         // LifecycleBeanPostProcessor needs Order. See https://issues.apache.org/jira/browse/SHIRO-222

         return order;

     }

 }