gettestanswersdistributionaction.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.awt.Font;
import java.io.ByteArrayOutputStream;
import java.util.*;
import javax.servlet.http.*;
import org.apache.struts.action.*;
import com.cyberdemia.school.*;
import com.cyberdemia.cybertester.*;
import java.util.logging.*;
import com.cyberdemia.cybertester.admin.*;
import com.cyberdemia.cybertester.common.*;
import org.jfree.chart.*;
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;

/**
 * 
 * GetTestAnswersDistributionAction is a Struts action to retrieve distribution of 
 * all users' answers for a test.
 *  
 * @author Alexander Yap
 */
public final class GetTestAnswersDistributionAction extends AbstractAdminAction 
{
	protected ActionForward doPerform(
		ActionMapping mapping, ActionForm form,
		HttpServletRequest request, HttpServletResponse response,
		HttpSession session) throws Exception
	{
		String ownerHierId = (String)session.getAttribute(AdminConstants.SELECTED_HIERARCHY_ID_KEY);
		if (ownerHierId==null)
		{
			ActionErrors errors = new ActionErrors();
			errors.add(ActionErrors.GLOBAL_ERROR, new ActionError("error.hierarchyNode.unselected"));
			saveErrors(request, errors);
			return mapping.findForward(Constants.ERROR);
		}

		Logger logger = CyberTesterUtils.getLogger();
		String testId = CyberTesterUtils.getParameterOrRequestAttribute(request,AdminConstants.TEST_ID_KEY);

		// Some forms will send in "NONE", convert it to null
		if ("NONE".equals(testId))
		{
			testId = null;
		}

		try
		{
			TestManagerHome tMgrHome = CyberTesterUtils.getTestManagerHome();
			TestManager testMgr = (TestManager)tMgrHome.create();
			TestData[] testList = testMgr.getTests(ownerHierId, true);
			request.setAttribute( AdminConstants.TEST_LIST_KEY, testList );

			if (testId!=null)
			{
				logger.fine("Retrieving answers distribution assigned to Test ID "+testId);
				request.setAttribute(AdminConstants.TEST_ID_KEY, testId);
				// Calculation various distributions by questions
				ReportGeneratorHome reportGenHome = CyberTesterUtils.getReportGeneratorHome();
				ReportGenerator reportGen = (ReportGenerator)reportGenHome.create();
				DefaultCategoryDataset answerDataset = new DefaultCategoryDataset();
				DefaultCategoryDataset percentageDataset = new DefaultCategoryDataset();
 				Map answersDistMap = reportGen.getAnswersDistributionForTest(testId);
 				Map percentageDistMap = reportGen.getScorePercentageDistributionForTest(testId, ReportGenerator.PERCENTAGE_BY_QUESTION);
 				Iterator quesIndexIter = answersDistMap.keySet().iterator();
				int maxAnswerCount = 20;
				while( quesIndexIter.hasNext())
 				{
 					Integer quesIndex = (Integer)quesIndexIter.next();
 					Integer answerDistVal = (Integer)answersDistMap.get(quesIndex);
					if (answerDistVal.intValue() > maxAnswerCount )
					{
						maxAnswerCount = answerDistVal.intValue();
					}
 					Double percentageDistVal = (Double)percentageDistMap.get(quesIndex);
					answerDataset.addValue(answerDistVal, "0", quesIndex);
					percentageDataset.addValue(percentageDistVal, "0", quesIndex);
				}

				JFreeChart answerDistChart = ChartFactory.createBarChart(
					"",
					"Question index", "Number of correct answers", answerDataset, PlotOrientation.VERTICAL, false, true, false);
				answerDistChart.setTitle(new TextTitle("Number of Correct Answers vs Questions", new Font("SansSerif",Font.BOLD, 12)));
				((CategoryAxis)answerDistChart.getCategoryPlot().getDomainAxis()).setVerticalCategoryLabels(true);
				ValueAxis rangeAxis = answerDistChart.getCategoryPlot().getRangeAxis();
				rangeAxis.setMaximumAxisValue(maxAnswerCount);
				rangeAxis.setMinimumAxisValue(0.0);
				CategoryItemRenderer renderer = answerDistChart.getCategoryPlot().getRenderer();
				renderer.setItemLabelGenerator(
					new  CategoryItemLabelGenerator()
					{
						public String generateItemLabel(CategoryDataset data, int series, int category)
						{
							return data.getValue(series, category).toString();
						}

						public String generateToolTip(CategoryDataset data, int series, int category)
						{
							return "Number of correct answers for question "+data.getColumnKey(category)+" : "+data.getValue(series, category).toString();
						}
					}
				);
				answerDistChart.setAntiAlias(true);
				
				JFreeChart percentageDistChart = ChartFactory.createBarChart(
					"",
					"Question index", "Percentage of correct answers", percentageDataset, PlotOrientation.VERTICAL, false, true, false);
				percentageDistChart.setTitle(new TextTitle("Percentage of Correct Answers vs Questions", new Font("SansSerif",Font.BOLD, 12)));
				((CategoryAxis)percentageDistChart.getCategoryPlot().getDomainAxis()).setVerticalCategoryLabels(true);
				rangeAxis = percentageDistChart.getCategoryPlot().getRangeAxis();
				rangeAxis.setMaximumAxisValue(100.0);
				rangeAxis.setMinimumAxisValue(0.0);
				renderer = percentageDistChart.getCategoryPlot().getRenderer();
				renderer.setItemLabelGenerator(
					new CategoryItemLabelGenerator()
					{
						public String generateItemLabel(CategoryDataset data, int series, int category)
						{
							return data.getValue(series, category).toString();
						}

						public String generateToolTip(CategoryDataset data, int series, int category)
						{
							return "Percentage of correct answers for question "+data.getColumnKey(category)+" : "+data.getValue(series, category).toString();
						}
					}
				);
				percentageDistChart.setAntiAlias(true);
				
				int width = Math.max(300, 100+(answerDataset.getColumnCount()*20));
				int height = 400;
				try
				{
					width = Integer.parseInt( request.getParameter("width") );
				}
				catch (NumberFormatException nfex)
				{ }
				try
				{
					height = Integer.parseInt( request.getParameter("height") );
				}
				catch (NumberFormatException nfex)
				{ }

				ByteArrayOutputStream baos = new ByteArrayOutputStream();
				ChartRenderingInfo info = new ChartRenderingInfo(new StandardEntityCollection());
				ChartUtilities.writeChartAsPNG( baos , answerDistChart,width, height, info );
				ChartDataCache cache = new ChartDataCache();
				cache.data = baos.toByteArray();
				cache.info = info;
				Map chartsCache = (Map)session.getAttribute(Constants.CHARTS_CACHE_KEY);
				String answerDistChartId = "C"+String.valueOf(System.currentTimeMillis());
				chartsCache.put(answerDistChartId, cache);
				request.setAttribute(AdminConstants.ANSWER_COUNT_DISTRIBUTION_CHART_ID_KEY, answerDistChartId );

				baos = new ByteArrayOutputStream();
				info = new ChartRenderingInfo(new StandardEntityCollection());
				ChartUtilities.writeChartAsPNG( baos , percentageDistChart,width, height, info );
				cache = new ChartDataCache();
				cache.data = baos.toByteArray();
				cache.info = info;
				String percentageDistChartId = "P"+String.valueOf(System.currentTimeMillis());
				chartsCache.put(percentageDistChartId, cache);
				request.setAttribute(AdminConstants.ANSWER_PERCENTAGE_DISTRIBUTION_CHART_ID_KEY, percentageDistChartId );

			}
			
		}
		catch (Exception ex)
		{
			logger.log( Level.SEVERE, "Error getting answers distribution", ex);
			throw ex;
		}
			
		return mapping.findForward(Constants.SUCCESS);
	}
	
}