getuserpercentagesdistributionaction.java

老外的在线考试

/*
 * CyberTester - J2EE Web application for creating, delivering and managing tests/exams/surveys.
 * Copyright (C) 2003 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.admin.report;

import java.util.*;
import java.io.ByteArrayOutputStream;
import java.awt.Font;
import javax.servlet.http.*;
import org.apache.struts.action.*;
import com.cyberdemia.school.*;
import com.cyberdemia.cybertester.*;
import com.cyberdemia.cybertester.common.*;
import java.util.logging.*;
import com.cyberdemia.cybertester.admin.*;
import org.jfree.chart.*;
import org.jfree.chart.title.*;
import org.jfree.data.*;
import org.jfree.chart.labels.*;
import org.jfree.chart.axis.*;
import org.jfree.chart.renderer.*;
import org.jfree.chart.entity.StandardEntityCollection;
import org.jfree.chart.plot.PlotOrientation;

/**
 *
 * GetUserPercentagesDistributionAction is a Struts action to retrieve distribution
 * of users' percentages.
 *
 * @author Alexander Yap, Nita Ambedkar
 */
public final class GetUserPercentagesDistributionAction extends AbstractAdminAction
{
    protected ActionForward doPerform(
        ActionMapping mapping, ActionForm form,
        HttpServletRequest request, HttpServletResponse response,
        HttpSession session) throws Exception
    {
        Logger logger = CyberTesterUtils.getLogger();
        try
        {

            DefaultCategoryDataset dataset = new DefaultCategoryDataset();
            // Calculation various distributions by questions
            ReportGeneratorHome reportGenHome = CyberTesterUtils.getReportGeneratorHome();
            ReportGenerator reportGen = (ReportGenerator)reportGenHome.create();
            Map distMap = reportGen.getScorePercentageDistributionByUsers(10.0);
            Iterator highValIter = distMap.keySet().iterator();
            int maxCount = 100;
            while (highValIter.hasNext())
            {
                Double highVal = (Double)highValIter.next();
                Integer count = (Integer)distMap.get(highVal);
                if (count.intValue() > maxCount)
                {
                    maxCount = count.intValue();
                }
                dataset.addValue(count, "0", highVal);
            }

            JFreeChart chart = ChartFactory.createBarChart(
                "",
                "Overall score %", "Number of users", dataset, PlotOrientation.VERTICAL, false, true, false);
            chart.setTitle(new TextTitle("User % Distribution", new Font("SansSerif",Font.BOLD, 12)));
            /*  Change for new version of JFree Chart 9.18 Change begin */
            ((CategoryAxis)chart.getCategoryPlot().getDomainAxis()).setCategoryLabelPositions(new CategoryLabelPositions());
            /*  Change for new version of JFree Chart 9.18 Change End */
            CategoryItemRenderer renderer = chart.getCategoryPlot().getRenderer();
            ValueAxis rangeAxis = chart.getCategoryPlot().getRangeAxis();
            /*  Change for new version of JFree Chart 9.18 Change begin */
            rangeAxis.setUpperBound((double)maxCount);
            rangeAxis.setLowerBound(0.0);
            renderer.setLabelGenerator(
                new CategoryLabelGenerator()
                {
                    public String generateLabel(CategoryDataset data, int series, int category)
                    {
                        return data.getValue(series, category).toString();
                    }
                }
            );
            /*  Change for new version of JFree Chart 9.18 Change End */

            chart.setAntiAlias(true);
            int width = 600;
            try
            {
                width = Integer.parseInt( request.getParameter("width") );
            }
            catch (NumberFormatException nfex)
            {
                // Ignore, width unchanged.
            }

            int height = 600;
            try
            {
                height = Integer.parseInt( request.getParameter("height") );
            }
            catch (NumberFormatException nfex)
            {
                // Ignore, height unchanged.
            }

            final ByteArrayOutputStream baos = new ByteArrayOutputStream();
            final ChartRenderingInfo info = new ChartRenderingInfo(new StandardEntityCollection());
            ChartUtilities.writeChartAsPNG( baos , chart,width, height, info );
            ChartDataCache cache = new ChartDataCache();
            cache.data = baos.toByteArray();
            cache.info = info;
            Map chartsCache = (Map)session.getAttribute(Constants.CHARTS_CACHE_KEY);
            String chartId = String.valueOf(System.currentTimeMillis());
            chartsCache.put(chartId, cache);
            request.setAttribute(Constants.CHART_ID_KEY, chartId );
            request.setAttribute(Constants.CHART_INFO_KEY, CyberTesterUtils.getImageMapAreaList(cache.info) );
        }
        catch (Exception ex)
        {
            logger.log( Level.SEVERE, "Error getting user percentages distribution", ex);
            throw ex;
        }

        return mapping.findForward(Constants.SUCCESS);
    }


}