/* ======================================================================
The Bodington System Software License, Version 1.0
  
Copyright (c) 2001 The University of Leeds.  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.

3.  The end-user documentation included with the redistribution, if any,
must include the following acknowledgement:  "This product includes
software developed by the University of Leeds
(http://www.bodington.org/)."  Alternately, this acknowledgement may
appear in the software itself, if and wherever such third-party
acknowledgements normally appear.

4.  The names "Bodington", "Nathan Bodington", "Bodington System",
"Bodington Open Source Project", and "The University of Leeds" must not be
used to endorse or promote products derived from this software without
prior written permission. For written permission, please contact
d.gardner@leeds.ac.uk.

5.  The name "Bodington" may not appear in the name of products derived
from this software without prior written permission of the University of
Leeds.

THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
WARRANTIES, INCLUDING, BUT NOT LIMITED TO,  TITLE,  THE IMPLIED WARRANTIES 
OF QUALITY  AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO 
EVENT SHALL THE UNIVERSITY OF LEEDS OR ITS 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.
=========================================================

This software was originally created by the University of Leeds and may contain voluntary 
contributions from others.  For more information on the Bodington Open Source Project, please 
see http://bodington.org/

====================================================================== */

package org.bodington.servlet;

import javax.servlet.http.*;
import java.text.SimpleDateFormat;
import java.util.TimeZone;
import java.util.Locale;
import java.util.Date;


/**
 * @author  bmb6jrm
 */
public class Response extends javax.servlet.http.HttpServletResponseWrapper
{
    
    HttpServletResponse wrapped_response;
    
    String html_body_class=null;

    /**
     * The date format we will use for creating date headers.
     * see setDateHeader method.
     * Locale US is one of many locales that would work OK.
     * It's only relevance is the spelling of day and month names
     */
    protected final SimpleDateFormat format =
        new SimpleDateFormat("EEE, dd MMM yyyy HH:mm:ss zzz",Locale.US);

    
    /** Creates new Response */
    public Response( HttpServletResponse response )
    {
	super( response );
	wrapped_response = response;
        format.setTimeZone(TimeZone.getTimeZone("GMT"));
    }

    
    public void setHtmlBodyClass( String s )
    {
	html_body_class = s;
    }
    
    public String getHtmlBodyClass()
    {
	return html_body_class;
    }
    
    /** Set appropriate headers in response to prevent caching of the page. */
    public void disableCaching()
    {
	// for HTTP 1.1
	setHeader( "Cache-Control", "no-cache" );
	
	// for HTTP 1.0
	setHeader( "Pragma", "no-cache" );
    }

    
    /**
     * Add the specified date header to the specified value.
     * See setDateHeader for explanation of why this method is here.
     *
     * @param name Name of the header to set
     * @param value Date value to be set
     */
    public void addDateHeader(String name, long value)
    {
        if (wrapped_response.isCommitted())
            return;

        wrapped_response.addHeader(name, format.format(new Date(value)));

    }

    /**
     * Set the specified date header to the specified value.
     * This has been added into wrapper because the iPlanet
     * implementation of HttpServletResponse gets it wrong
     * by putting local time into the header although HTTP
     * requires GMT time.
     *
     * @param name Name of the header to set
     * @param value Date value to be set
     */
    public void setDateHeader(String name, long value)
    {
        if ( wrapped_response.isCommitted() )
            return;

        wrapped_response.setHeader(name, format.format(new Date(value)));
    }


}