// HttpServlet - the HTTP servlet class//// API based on documentation from JavaSoft.//// Copyright (C) 1996,1998 by Jef Poskanzer <jef@acme.com>. All rights reserved.//// Redistribution and use in source and binary forms, with or without// modification, are permitted provided that the following conditions// are met:// 1. Redistributions of source code must retain the above copyright//    notice, this list of conditions and the following disclaimer.// 2. Redistributions in binary form must reproduce the above copyright//    notice, this list of conditions and the following disclaimer in the//    documentation and/or other materials provided with the distribution.//// THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE// ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS// OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)// HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT// LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY// OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF// SUCH DAMAGE.//// Visit the ACME Labs Java page for up-to-date versions of this and other// fine Java utilities: http://www.acme.com/java/package Acme.Serve.servlet.http;import java.io.*;import Acme.Serve.servlet.*;/// The HTTP servlet class.// <P>// HttpServlets are little Java programs that can be hooked into an HTTP// server and run in response to URLs.// <P>// This is taken from JavaSoft's Servlet API documentation.// <P>// <A HREF="/resources/classes/Acme/Serve/servlet/http/HttpServlet.java">Fetch the software.</A><BR>// <A HREF="/resources/classes/Acme.tar.gz">Fetch the entire Acme package.</A>// <P>// @see Acme.Serve.SampleServlet// @see Acme.Serve.Servepublic abstract class HttpServlet extends GenericServlet implements Serializable    {    /// Services a single HTTP request from the client.    // @param req the HTTP request    // @param req the HTTP response    // @exception ServletException when a Servlet exception has occurred    // @exception IOException when an I/O exception has occurred    public abstract void service( HttpServletRequest req, HttpServletResponse res ) throws ServletException, IOException;    /// Services a single generic request from the client.    // (This is required by the peculiar inheritance structure.)    // @param req the servlet request    // @param req the servlet response    // @exception ServletException when a Servlet exception has occurred    // @exception IOException when an I/O exception has occurred    public void service( ServletRequest req, ServletResponse res ) throws ServletException, IOException	{	try	    {	    service( (HttpServletRequest) req, (HttpServletResponse) res );	    }	catch ( ClassCastException e )	    {	    throw new ServletException( "not an HTTP request" );	    }	}    }