/*
* Copyright (c) 1998-2011 Caucho Technology -- all rights reserved
*
* This file is part of Resin(R) Open Source
*
* Each copy or derived work must preserve the copyright notice and this
* notice unmodified.
*
* Resin Open Source 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 2 of the License, or
* (at your option) any later version.
*
* Resin Open Source 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, or any warranty
* of NON-INFRINGEMENT. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License
* along with Resin Open Source; if not, write to the
* Free SoftwareFoundation, Inc.
* 59 Temple Place, Suite 330
* Boston, MA 02111-1307 USA
*
* @author Scott Ferguson
*/
package com.caucho.filters;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.transaction.UserTransaction;
import java.io.IOException;
/**
* Wraps the request in a transaction. All database calls for
* the request will either succeed together or fail.
*
* @since Resin 2.0.5
*/
public class TransactionFilter implements Filter {
/**
* The UserTransaction object.
*/
private UserTransaction _userTransaction;
/**
* Lookup java:comp/UserTransaction and cache the results.
*/
public void init(FilterConfig config)
throws ServletException
{
try {
Context ic = (Context) new InitialContext();
_userTransaction = (UserTransaction) ic.lookup("java:comp/UserTransaction");
} catch (NamingException e) {
throw new ServletException(e);
}
}
/**
* Wrap the request in a transaction. If the request returns normally,
* the transaction will commit. If an exception is thrown it will
* rollback.
*/
public void doFilter(ServletRequest request, ServletResponse response,
FilterChain nextFilter)
throws ServletException, IOException
{
try {
_userTransaction.begin();
nextFilter.doFilter(request, response);
_userTransaction.commit();
} catch (ServletException e) {
rollback();
throw e;
} catch (IOException e) {
rollback();
throw e;
} catch (RuntimeException e) {
rollback();
throw e;
} catch (Throwable e) {
rollback();
throw new ServletException(e);
}
}
/**
* Rolls the request back.
*/
private void rollback()
throws ServletException
{
try {
_userTransaction.rollback();
} catch (Exception e) {
throw new ServletException(e);
}
}
/**
* Any cleanup for the filter.
*/
public void destroy()
{
}
}