/*
 * Copyright (C) 2005-2010 Alfresco Software Limited.
 *
 * This file is part of Alfresco
 *
 * Alfresco is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Alfresco is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Alfresco. If not, see <http://www.gnu.org/licenses/>.
 */
package org.alfresco.util;

import org.springframework.beans.BeansException;
import org.springframework.beans.factory.xml.BeanDefinitionParserDelegate;
import org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader;
import org.springframework.beans.factory.xml.XmlBeanDefinitionReader;
import org.springframework.beans.factory.xml.XmlReaderContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.w3c.dom.Element;

/**
 * A wrapper around {@link ClassPathXmlApplicationContext} which forces
 *  all beans to be loaded lazily.
 * You shouldn't do this in production, but it can be handy with
 *  unit tests, as it allows a quicker startup when you don't touch
 *  much of the application.
 *  
 * @author Nick Burch
 */
public class LazyClassPathXmlApplicationContext extends
      ClassPathXmlApplicationContext {
   
   public LazyClassPathXmlApplicationContext(String[] configLocations)
         throws BeansException {
      super(configLocations);
   }

   protected void initBeanDefinitionReader(XmlBeanDefinitionReader reader) {
      super.initBeanDefinitionReader(reader);
      
      postInitBeanDefinitionReader(reader);
   }
    
   /**
    * Does the work of enabling Lazy Init on the xml bean reader
    */
   protected static void postInitBeanDefinitionReader(XmlBeanDefinitionReader reader) {
      reader.setDocumentReaderClass(AlwaysLazyInitBeanDefinitionDocumentReader.class);
   }

   protected static class AlwaysLazyInitBeanDefinitionDocumentReader extends DefaultBeanDefinitionDocumentReader {
      @Override
      protected BeanDefinitionParserDelegate createHelper(
            XmlReaderContext readerContext, Element root) {
         BeanDefinitionParserDelegate helper = super.createHelper(readerContext, root);
         helper.getDefaults().setLazyInit("true");
         return helper;
      }
   }
}