/*
* 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.server.dispatch;
import javax.servlet.FilterChain;
import javax.servlet.Servlet;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.UnavailableException;
import java.io.IOException;
/**
* Represents the final servlet in a filter chain.
*/
public class SingleThreadServletFilterChain implements FilterChain {
// servlet config
private ServletConfigImpl _config;
// servlet
private Servlet _servlet;
/**
* Create the filter chain servlet.
*
* @param servlet the underlying servlet
*/
public SingleThreadServletFilterChain(ServletConfigImpl config)
{
if (config == null)
throw new NullPointerException();
_config = config;
}
/**
* Invokes the final servlet at the end of the chain.
*
* @param request the servlet request
* @param response the servlet response
*
* @since Servlet 2.3
*/
public void doFilter(ServletRequest request,
ServletResponse response)
throws ServletException, IOException
{
Servlet servlet = null;
synchronized (this) {
servlet = _servlet;
_servlet = null;
}
if (servlet == null) {
try {
servlet = (Servlet) _config.createServlet(true);
} catch (ServletException e) {
throw e;
} catch (Exception e) {
throw new ServletException(e);
}
}
try {
servlet.service(request, response);
} catch (UnavailableException e) {
_config.setInitException(e);
// application.killServlet(servlet, config);
throw e;
}
synchronized (this) {
if (_servlet == null) {
_servlet = servlet;
servlet = null;
}
}
if (servlet != null)
servlet.destroy();
}
}