/*

  * Copyright 2005-2008 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.core.resourceloader;

 import javax.xml.namespace.QName;

 import org.apache.commons.lang.StringUtils;

 import org.apache.log4j.Logger;

 import org.kuali.rice.core.config.ConfigurationException;

 import org.springframework.context.ApplicationContext;

 import org.springframework.context.ConfigurableApplicationContext;

 import org.springframework.context.support.ClassPathXmlApplicationContext;

 /**

  * A simple {@link ResourceLoader} which wraps a Spring {@link ConfigurableApplicationContext}.

  *

  * Starts and stops the {@link ConfigurableApplicationContext}.

  * 

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

  */

 public class SpringResourceLoader extends BaseResourceLoader {

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

         private SpringResourceLoader parentSpringResourceLoader;

         private ApplicationContext parentContext;

         private ConfigurableApplicationContext context;

         private final String[] fileLocs;

         public SpringResourceLoader(QName name, String fileLoc) {

             this(name, new String[] { fileLoc });

         }

         public SpringResourceLoader(QName name, String[] fileLocs) {

                 super(name);

                 this.fileLocs = fileLocs;

         }

         public Object getService(QName serviceName) {

                     if (!isStarted()) {

                         return null;

                     }

                 if (this.getContext().containsBean(serviceName.toString())) {

                         Object service = this.getContext().getBean(serviceName.toString());

                         return postProcessService(serviceName, service);

                 }

                 return super.getService(serviceName);

         }

         @Override

         public void start() throws Exception {

                 if(!isStarted()){

                         LOG.info("Creating Spring context " + StringUtils.join(this.fileLocs, ","));

                         if (parentSpringResourceLoader != null && parentContext != null) {

                                 throw new ConfigurationException("Both a parentSpringResourceLoader and parentContext were defined.  Only one can be defined!");

                         }

                         if (parentSpringResourceLoader != null) {

                                 parentContext = parentSpringResourceLoader.getContext();

                         }

                         this.context = new ClassPathXmlApplicationContext(this.fileLocs, parentContext);

                         super.start();

                 }

         }

         @Override

         public void stop() throws Exception {

                 LOG.info("Stopping Spring context " + StringUtils.join(this.fileLocs, ","));

                 this.context.close();

                 super.stop();

         }

         public ConfigurableApplicationContext getContext() {

                 return this.context;

         }

         public void setParentContext(ApplicationContext parentContext) {

                 this.parentContext = parentContext;

         }

         public void setParentSpringResourceLoader(

                         SpringResourceLoader parentSpringResourceLoader) {

                 this.parentSpringResourceLoader = parentSpringResourceLoader;

         }

 }