/*
    * EL4J, the Extension Library for the J2EE, adds incremental enhancements to
    * the spring framework, http://el4j.sf.net
    * Copyright (C) 2009 by ELCA Informatique SA, Av. de la Harpe 22-24,
    * 1000 Lausanne, Switzerland, http://www.elca.ch
    *
    * EL4J is published under the GNU Lesser General Public License (LGPL)
    * Version 2.1. See http://www.gnu.org/licenses/
    *
   * This program 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 Lesser General Public License for more details.
   *
   * For alternative licensing, please contact info@elca.ch
   */
  package ch.elca.el4j.services.remoting.jaxb.hibernate;
  
  import java.lang.reflect.Field;
  import java.lang.reflect.Method;
  
  import javax.xml.bind.JAXBException;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import com.sun.xml.bind.AccessorFactory;
  import com.sun.xml.bind.AccessorFactoryImpl;
  import com.sun.xml.bind.v2.runtime.reflect.Accessor;
  
  /**
   * A JAXB Accessor factory that uses {@link HibernateJAXBAccessor} if possible.
   *
   * @svnLink $Revision: 3945 $;$Date: 2009-10-16 09:31:52 +0200 (Fr, 16. Okt 2009) $;$Author: swismer $;$URL: https://el4j.svn.sourceforge.net/svnroot/el4j/branches/el4j_3_1/el4j/framework/modules/remoting_jaxws/src/main/java/ch/elca/el4j/services/remoting/jaxb/hibernate/HibernateJAXBAccessorFactory.java $
   *
   * @author clemenb (see https://forum.hibernate.org/viewtopic.php?f=1&t=998896)
   */
  public class HibernateJAXBAccessorFactory implements AccessorFactory {
  
  	/**
  	 * The delegate accessor factory.
  	 */
  	private final AccessorFactory delegate;
  
  	/**
  	 * The method to call for checking if value is uninitialized.
  	 */
  	private Method hibernateInitializationCheck;
  
  	/**
  	 * Create a new AccessorFactory that never throws LazyInitializationException during (un)marshaling.
  	 */
  	public HibernateJAXBAccessorFactory() {
  		this(AccessorFactoryImpl.getInstance());
  	}
  
  	/**
  	 * @param delegate    the delegate accessor factory
  	 */
  	@SuppressWarnings("unchecked")
  	public HibernateJAXBAccessorFactory(AccessorFactory delegate) {
  		this.delegate = delegate;
  		try {
  			Class hibernate = Class.forName("org.hibernate.Hibernate");
  			hibernateInitializationCheck = hibernate.getMethod("isInitialized", Object.class);
  			Logger logger = LoggerFactory.getLogger(HibernateJAXBAccessorFactory.class);
  			logger.info("Detected Hibernate: Enabled "
  				+ "hiding of uninitialized lazy objects and collections during XML marshalling.");
  		} catch (ClassNotFoundException e) {
  			hibernateInitializationCheck = null;
  			Logger logger = LoggerFactory.getLogger(HibernateJAXBAccessorFactory.class);
  			logger.info("Hibernate was not detected: Disabled "
  				+ "hiding of uninitialized lazy objects and collections during XML marshalling.");
  		} catch (Exception e) {
  			hibernateInitializationCheck = null;
  			Logger logger = LoggerFactory.getLogger(HibernateJAXBAccessorFactory.class);
  			logger.warn("Detected Hibernate, but failed "
  				+ "to enable hiding of uninitialized lazy objects and collections during XML marshalling.", e);
  		}
  	}
  
  	@SuppressWarnings("unchecked")
  	@Override
  	public Accessor createFieldAccessor(Class bean, Field field, boolean readOnly) throws JAXBException {
  		Accessor accessor = delegate.createFieldAccessor(bean, field, readOnly);
  
  		if (hibernateInitializationCheck == null) {
  			return accessor;
  		} else {
  			return new HibernateJAXBAccessor(accessor, hibernateInitializationCheck);
  		}
  	}
  
  	@SuppressWarnings("unchecked")
  	@Override
  	public Accessor createPropertyAccessor(Class bean, Method getter, Method setter) throws JAXBException {
  		Accessor accessor = delegate.createPropertyAccessor(bean, getter, setter);
  
  		if (hibernateInitializationCheck == null) {
 			return accessor;
 		} else {
 			return new HibernateJAXBAccessor(accessor, hibernateInitializationCheck);
 		}
 	}
 }