import java.io.IOException;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hibernate.FlushMode;
import org.hibernate.classic.Session;
import org.hibernate.context.ManagedSessionContext;
import org.hibernate.SessionFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.dao.DataAccessResourceFailureException;
import org.springframework.orm.hibernate3.SessionFactoryUtils;
import org.springframework.orm.hibernate3.SessionHolder;
import org.springframework.transaction.support.TransactionSynchronizationManager;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;
import org.springframework.web.filter.OncePerRequestFilter;

public class OpenSessionInJobBinder {

   protected final Log logger = LogFactory.getLog(getClass());

   public static final String DEFAULT_SESSION_FACTORY_BEAN_NAME = "sessionFactory";

   private String sessionFactoryBeanName = DEFAULT_SESSION_FACTORY_BEAN_NAME;

   private boolean singleSession = true;

   public static final String HIBERNATE_SESSION_KEY = "hibernateSession";

   public static final String END_OF_CONVERSATION_FLAG = "endOfConversation";

   boolean participate = false;

   public void setSessionFactoryBeanName(String sessionFactoryBeanName) {
      this.sessionFactoryBeanName = sessionFactoryBeanName;
   }

   protected String getSessionFactoryBeanName() {
      return sessionFactoryBeanName;
   }

   public void setSingleSession(boolean singleSession) {
      this.singleSession = singleSession;
   }

   protected boolean isSingleSession() {
      return singleSession;
   }

   public void doBind(Session session, ApplicationContext ctx) {
      SessionFactory sessionFactory = lookupSessionFactory(ctx);
      ManagedSessionContext.bind(session);
      participate = false;
      if (isSingleSession()) {
         if (TransactionSynchronizationManager.hasResource(sessionFactory)) {
            participate = true;
         } else {
            logger.info("Opening single Hibernate Session in OpenSessionInJobBinder");
            TransactionSynchronizationManager.bindResource(sessionFactory, new SessionHolder(session));
         }
      } else {
         if (SessionFactoryUtils.isDeferredCloseActive(sessionFactory)) {
            participate = true;
         } else {
            SessionFactoryUtils.initDeferredClose(sessionFactory);
         }
      }
   }

   public Session doUnBind(Session session, ApplicationContext ctx, boolean end) {
      SessionFactory sessionFactory = lookupSessionFactory(ctx);
      try {
         session = ManagedSessionContext.unbind(sessionFactory);
      }

      finally {
         SessionHolder sessionHolder = (SessionHolder) TransactionSynchronizationManager.getResource(sessionFactory);
         if (end) {
            if (isSingleSession()) {
               // single session mode
               TransactionSynchronizationManager.unbindResource(sessionFactory);
               try {
                  closeSession(session, sessionFactory);
               } catch (RuntimeException ex) {
               }
            } else {
               SessionFactoryUtils.processDeferredClose(sessionFactory);
            }
            session = null;
         } else {

         }
      }
      return session;
   }

   protected SessionFactory lookupSessionFactory(ApplicationContext ctx) {
      return (SessionFactory) ctx.getBean(getSessionFactoryBeanName(), SessionFactory.class);

   }
   protected void closeSession(Session session, SessionFactory sessionFactory) {
      SessionFactoryUtils.releaseSession(session, sessionFactory);
   }

}