edu.sc.seis.receiverFunction.web.MyDisplayChart.java Source code

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Here is the source code for edu.sc.seis.receiverFunction.web.MyDisplayChart.java

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package edu.sc.seis.receiverFunction.web;

import org.jfree.chart.servlet.ChartDeleter;
import org.jfree.chart.servlet.ServletUtilities;

/* ===========================================================
* JFreeChart : a free chart library for the Java(tm) platform
 * ===========================================================
  *
  * (C) Copyright 2000-2007, by Object Refinery Limited and Contributors.
  *
  * Project Info:  http://www.jfree.org/jfreechart/index.html
  *
  * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 
* USA.  
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc. 
* in the United States and other countries.]
*
* -----------------
* DisplayChart.java
* -----------------
* (C) Copyright 2002-2007, by Richard Atkinson and Contributors.
*
* Original Author:  Richard Atkinson;
* Contributor(s):   David Gilbert (for Object Refinery Limited);
*
* $Id: DisplayChart.java,v 1.2.2.3 2007/02/02 15:03:19 mungady Exp $
*
* Changes
* -------
* 19-Aug-2002 : Version 1;
* 09-Mar-2005 : Added facility to serve up "one time" charts - see 
*               ServletUtilities.java (DG);
* ------------- JFREECHART 1.0.x ---------------------------------------------
* 02-Feb-2007 : Removed author tags all over JFreeChart sources (DG);
*
*/

import java.io.File;
import java.io.IOException;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

/**
 * Servlet used for streaming charts to the client browser from the temporary
 * directory.  You need to add this servlet and mapping to your deployment 
 * descriptor (web.xml) in order to get it to work.  The syntax is as follows:
 * <xmp>
 * <servlet>
 *    <servlet-name>DisplayChart</servlet-name>
 *    <servlet-class>org.jfree.chart.servlet.DisplayChart</servlet-class>
 * </servlet>
 * <servlet-mapping>
 *     <servlet-name>DisplayChart</servlet-name>
 *     <url-pattern>/servlet/DisplayChart</url-pattern>
 * </servlet-mapping>
 * </xmp>
 */

public class MyDisplayChart extends HttpServlet {

    /**
     * Default constructor.
     */
    public MyDisplayChart() {
        super();
    }

    /**
     * Init method.
     *
     * @throws ServletException never.
     */
    public void init() throws ServletException {
        return;
    }

    /**
     * Service method.
     *
     * @param request  the request.
     * @param response  the response.
     *
     * @throws ServletException ??.
     * @throws IOException ??.
     */
    public void service(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {

        HttpSession session = request.getSession();
        String filename = request.getParameter("filename");

        if (filename == null) {
            throw new ServletException("Parameter 'filename' must be supplied");
        }
        logger.debug("service :" + filename);
        //  Replace ".." with ""
        //  This is to prevent access to the rest of the file system
        filename = ServletUtilities.searchReplace(filename, "..", "");

        //  Check the file exists
        File file = new File(System.getProperty("java.io.tmpdir"), filename);
        if (!file.exists()) {
            throw new ServletException("File '" + file.getAbsolutePath() + "' does not exist");
        }

        //  Check that the graph being served was created by the current user
        //  or that it begins with "public"
        boolean isChartInUserList = false;
        ChartDeleter chartDeleter = (ChartDeleter) session.getAttribute("JFreeChart_Deleter");
        if (chartDeleter != null) {
            isChartInUserList = chartDeleter.isChartAvailable(filename);
        }

        boolean isChartPublic = false;
        if (filename.length() >= 6) {
            if (filename.substring(0, 6).equals("public")) {
                isChartPublic = true;
            }
        }

        boolean isOneTimeChart = false;
        if (filename.startsWith(ServletUtilities.getTempOneTimeFilePrefix())) {
            isOneTimeChart = true;
        }
        //
        // WARNING: HACK AHEAD!!!!!
        //
        // this is dumb, but since all ears charts are public and one time, just serve it
        // I think the upgrade to jetty8 caused the http to no longer have sessions, so
        // the default DisplayChart servlet had all three of 
        // isChartInUserList || isChartPublic || isOneTimeChart false, and
        // so no image was served. Progress! :(
        isOneTimeChart = true;

        if (isChartInUserList || isChartPublic || isOneTimeChart) {
            //  Serve it up
            logger.debug("sending " + file);
            ServletUtilities.sendTempFile(file, response);
            if (isOneTimeChart) {
                logger.debug("delelte " + file);
                file.delete();
            }
        } else {
            logger.error("chart image not found " + filename);
            throw new ServletException("Chart image not found");
        }
        return;
    }

    private static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(MyDisplayChart.class);
}