Method of Realizing Line Graph of Graphic Report by JavaWeb

In this paper, the method of realizing line chart of graphic report by JavaWeb is described with examples. Share it for your reference, as follows:

Step Description:

1. Import four jar packages: log4j. jar, jfreechart-0. 9.18. jar, jdom. jar, jcommon-0. 9.3. jar

2. Write the Tuxin. Java class in a package

package com.mengya.util;
import java.awt.Color;
import java.awt.Font;
import java.io.PrintWriter;
import javax.servlet.http.HttpSession;
import org.jfree.chart.ChartFactory;
import org.jfree.chart.ChartRenderingInfo;
import org.jfree.chart.ChartUtilities;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.StandardLegend;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.entity.StandardEntityCollection;
import org.jfree.chart.plot.CategoryPlot;
import org.jfree.chart.plot.PlotOrientation;
import org.jfree.chart.renderer.LineAndShapeRenderer;
import org.jfree.chart.servlet.ServletUtilities;
import org.jfree.data.DefaultCategoryDataset;
public class Line
{
  private DefaultCategoryDataset dataset = new DefaultCategoryDataset();
  public void setValue(int sum, String line, String wfield)
  {
   dataset.addValue(sum, line, wfield);
  }
  public String generateLineChart(String title,String wfield, String hfield, HttpSession session, PrintWriter pw,int wPhoto,int hPhoto)
  {
   String filename = null;
  try
   {
     final JFreeChart chart = ChartFactory.createLineChart
      (
       title, //  Chart title 
       wfield, //  Display label of horizontal axis 
       hfield, //  Display label of vertical axis 
       dataset, // Data set 
       PlotOrientation.VERTICAL, //  Chart Direction: Horizontal, Vertical 
       true, //  Display Legend 
       true, //  Whether to generate prompt tools  tooltips
       false //  Whether to generate URL Link 
     );
     StandardLegend legend = (StandardLegend) chart.getLegend();// Generate Legend 
     legend.setDisplaySeriesShapes(true);// Show Legend Shapes 
     legend.setShapeScaleX(1.5);// Set Legend X Size of Axis 
     legend.setShapeScaleY(1.5);// Set Legend Y Size of Axis 
     legend.setDisplaySeriesLines(true);// Displays the horizontal line of the icon item 
     // Set the background color of the picture 
     chart.setBackgroundPaint(new java.awt.Color(189,235,255));
     CategoryPlot plot = (CategoryPlot) chart.getPlot();
     plot.setBackgroundPaint(new Color(239,251,255));// Generate the background color of the wall in the picture 
     plot.setRangeGridlinePaint(Color.black);// Generate the color of grid lines in the picture 
     //  Message displayed when there is no data 
     plot.setNoDataMessage(" There are no relevant statistics ");
     plot.setNoDataMessageFont(new Font(" Blackbody ", Font.CENTER_BASELINE, 16));
     plot.setNoDataMessagePaint(Color.RED);
     NumberAxis rangeAxis = (NumberAxis) plot.getRangeAxis();
     rangeAxis.setStandardTickUnits(NumberAxis.createIntegerTickUnits());// Set the units of tick marks in the diagram 
     rangeAxis.setAutoRangeIncludesZero(true);// Force inclusion in the automatically selected data range 0
     LineAndShapeRenderer renderer = (LineAndShapeRenderer) plot.getRenderer();
     renderer.setDrawShapes(true);// The data points of polygonal lines use different shapes according to classification 
     renderer.setItemLabelsVisible(true);// Prompt tool that displays the data value at each point , Is the data label visible 
     ChartRenderingInfo info = new ChartRenderingInfo(new
       StandardEntityCollection());
     //500 Is the length of the picture, 300 Is the height of the picture 
     filename = ServletUtilities.saveChartAsPNG(chart, wPhoto, hPhoto, info, session);
     ChartUtilities.writeImageMap(pw, filename, info);
     pw.flush();
   }
   catch(Exception e)
   {
   e.printStackTrace();
   }
   return filename;
  }
}

3. Configure web. xml and add the following inner space in web. xml:

<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>/DisplayChart</url-pattern>
</servlet-mapping>

4. Add content to the jsp where you want to display the picture:

<%@ page language="java" import="java.util.*,com.mengya.util.Line,com.mengya.bean.StuBean" pageEncoding="gbk"%>
<%@page import="java.io.PrintWriter;"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
 <head>
 <title> Line chart </title>
 </head>
 <body>
 <%
  Line tt = new Line();
  // No. 1 1 Broken line 
  List ar = (ArrayList) request.getAttribute("arr1");
  for (int i = 0; i < ar.size(); i++) {
  StuBean bean = (StuBean) ar.get(i);
  tt.setValue((int) bean.getS_money(), " Zhang Mingxue's Personal Consumption Proportion Chart ", bean.getS_month()+ "");
  }
  // Article 2 Broken line 
  ar = (ArrayList) request.getAttribute("arr2");
  for (int i = 0; i < ar.size(); i++) {
  StuBean bean = (StuBean) ar.get(i);
  tt.setValue((int) bean.getS_money(), " Mengya Personal Consumption Proportion Chart ", bean.getS_month()+ "");
  }
  // Description :tt.setValue(int a,String b,String c)
  // Among them, the first 2 Parameters b Is the name of the broken line , It is best not to have the name of each broken line 1 Sample .
  String filename = tt.generateLineChart(" Personal consumption ratio chart ", " Month     Portions ",
   " Fee     Use ", session, new PrintWriter(out), 800, 550);
  String graphURL = request.getContextPath()
   + "/DisplayChart?filename=" + filename;
 %>
 <P ALIGN="CENTER">
 <img src="<%=graphURL %>" width=800 height=550 border=1 usemap="#<%=filename%>">
 </body>
</html>

I hope this article is helpful to everyone's JSP programming.