/* ================================================================
* Cewolf : Chart enabling Web Objects Framework
* ================================================================
*
* Project Info: http://cewolf.sourceforge.net
* Project Lead: Guido Laures (guido@laures.de);
*
* (C) Copyright 2002, by Guido Laures
*
* This library is free software; you can redistribute it and/or modify it under the terms
* of the GNU Lesser General Public License as published by the Free Software Foundation;
* either version 2.1 of the License, or (at your option) any later version.
*
* This library 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307, USA.
*/
package de.laures.cewolf.storage;
import java.io.Serializable;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import javax.servlet.jsp.PageContext;
import de.laures.cewolf.CewolfException;
import de.laures.cewolf.ChartImage;
import de.laures.cewolf.Storage;
import de.laures.cewolf.taglib.util.KeyGenerator;
/**
* Storage stores images in session, but expires them after a certain time.
* This expiration time defaults to 300 seconds, and can be changed by adding
* the timeout="xxx" parameter to <cewolf:img> and <cewolf:legend> tags.
*
* @author brianf
*/
public class LongTermSessionStorage implements Storage
{
static final long serialVersionUID = 6810872505939693581L;
public final String getKey( ChartImage cid )
{
return String.valueOf(KeyGenerator.generateKey((Serializable) cid));
}
/*
* (non-Javadoc)
*
* @see de.laures.cewolf.Storage#storeChartImage(de.laures.cewolf.ChartImage, javax.servlet.jsp.PageContext)
*/
public String storeChartImage( ChartImage chartImage, PageContext pageContext ) throws CewolfException
{
HttpSession session = pageContext.getSession();
SessionStorageGroup ssg = (SessionStorageGroup) session.getAttribute("CewolfCharts");
if ( ssg == null )
{
ssg = new SessionStorageGroup();
session.setAttribute("CewolfCharts", ssg);
}
String cid = getKey(chartImage);
SessionStorageItem ssi = new SessionStorageItem(chartImage, cid, chartImage.getTimeoutTime());
ssg.put(cid, ssi);
return cid;
}
/*
* (non-Javadoc)
*
* @see de.laures.cewolf.Storage#getChartImage(java.lang.String, javax.servlet.http.HttpServletRequest)
*/
public ChartImage getChartImage( String id, HttpServletRequest request )
{
HttpSession session = request.getSession();
ChartImage chart = null;
SessionStorageGroup ssg = (SessionStorageGroup) session.getAttribute("CewolfCharts");
if ( ssg != null )
{
SessionStorageItem ssi = (SessionStorageItem) ssg.get(id);
if ( ssi != null )
{
chart = ssi.getChart();
}
}
return chart;
}
/*
* (non-Javadoc)
*
* @see de.laures.cewolf.Storage#init(javax.servlet.ServletContext)
*/
public void init( ServletContext servletContext ) throws CewolfException {
}
/**
* @see de.laures.cewolf.Storage#removeChartImage(java.lang.String, javax.servlet.http.HttpServletRequest)
*/
public String removeChartImage(String cid, HttpServletRequest request) throws CewolfException {
HttpSession session = request.getSession();
// No session exit
if (session == null)
{
return cid;
}
SessionStorageGroup ssg = (SessionStorageGroup) session.getAttribute("CewolfCharts");
if ( ssg == null )
{
// No group exit
return cid;
}
ssg.remove(cid);
return cid;
}
}