abstractuseraction.java

老外的在线考试

/*
 * CyberTester - J2EE Web application for creating, delivering and managing tests/exams/surveys. 
 * Copyright (C) 2004 CyberDemia Research and Services Pty Ltd
 *
 * This program 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.
 *
 * This program 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.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program (see the file COPYING); if not, write to the
 * Free Software Foundation, Inc.,
 * 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * See the COPYING file located in the top-level-directory of
 * the archive of this program for complete text of license.
 */
package com.cyberdemia.cybertester;

import java.util.Locale;

import javax.servlet.http.*;
import org.apache.struts.Globals;
import org.apache.struts.action.*;

/**
* Abstract base class for Struts actions within CyberTester protected areas
* (areas requiring login). It ensures that a valid user session is present before
* calling the abstract method <code>doPerform(...)</code>.
* The concrete subclass must implement <code>doPerform(...)</code> to perform
* the normal Struts action.
*
* @version $Revision: 1.4 $ at $Date: 2004/03/29 14:55:42 $ by $Author: alexycyap $
* @author Alexander Yap
*/
public abstract class AbstractUserAction extends Action
{
	public ActionForward execute(ActionMapping mapping, ActionForm form,
		HttpServletRequest request, HttpServletResponse response)
		throws Exception
	{
		HttpSession session = CyberTesterUtils.getUserSession(request);
		if (session==null)
		{
			return mapping.findForward(Constants.TIMEOUT);
		}

		ActionForward actForward = null;
		try
		{
			actForward = doPerform(mapping, form, request, response, session);
		}
		catch (Exception th)
		{
			request.setAttribute( Globals.EXCEPTION_KEY, th );
			throw th;
		}
		return actForward;
	}

	/**
	* Subclass must implement this with the normal Struts action code.
	* i.e. what normally goes into the <code>perform()</code> method of a standard Struts Action.
	*/
	protected abstract ActionForward doPerform(
		ActionMapping mapping, ActionForm form,
		HttpServletRequest request, HttpServletResponse response,
		HttpSession session) throws Exception;


	protected Locale getSessionLocale(HttpSession session)
	{
		Locale locale = (Locale)session.getAttribute(Globals.LOCALE_KEY);
		if (locale==null)
		{
			locale = Locale.getDefault();
		}
		return locale;
	}


}