NotModifiedAction.java

/*
 * NotModifiedAction.java
 *
 * Version: $Revision: 3705 $
 *
 * Date: $Date: 2009-04-11 13:02:24 -0400 (Sat, 11 Apr 2009) $
 *
 * Copyright (c) 2002, Hewlett-Packard Company and Massachusetts
 * Institute of Technology.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * - Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *
 * - 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.
 *
 * - Neither the name of the Hewlett-Packard Company nor the name of the
 * Massachusetts Institute of Technology nor the names of their
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
 * HOLDERS 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.
 */
package org.dspace.app.xmlui.aspect.general;

import java.util.HashMap;
import java.util.Map;

import javax.servlet.http.HttpServletResponse;

import org.apache.avalon.framework.parameters.Parameters;
import org.apache.cocoon.acting.AbstractAction;
import org.apache.cocoon.environment.ObjectModelHelper;
import org.apache.cocoon.environment.Redirector;
import org.apache.cocoon.environment.SourceResolver;
import org.apache.cocoon.environment.http.HttpEnvironment;

/**
 * Simple action to return a 304 (Not Modified) status, for when request
 * had the If-modified-since header and resource has not been modified.
 * Used in conjunction with IfModifiedSinceSelector
 *
 * @author Larry Stone
 */

public class NotModifiedAction extends AbstractAction
{
    /**
     * Return a 304 (Not Modified) status in the response.
     */
    public Map act(Redirector redirector, SourceResolver resolver, Map objectModel,
            String source, Parameters parameters) throws Exception
    {
        final HttpServletResponse httpResponse = (HttpServletResponse) objectModel.get(HttpEnvironment.HTTP_RESPONSE_OBJECT);
        httpResponse.sendError(HttpServletResponse.SC_NOT_MODIFIED);
        return new HashMap();
    }
}