JfreeChart的简单应用
1.在web project 中加入jar
jcommon-1.0.16.jar
jfreechart-1.0.13.jar
2.在web中配置 JfreeChart
<?xml version="1.0" encoding="UTF-8"?><web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"><servlet> <servlet-name>jcPie</servlet-name> <servlet-class>com.sh.servlet.jcPie</servlet-class></servlet> <servlet-mapping> <servlet-name>jcPie</servlet-name> <url-pattern>/servlet/jcPie</url-pattern> </servlet-mapping><!--配置 JfreeChart--><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> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list></web-app>
3.编写 jcPie servlet
package com.sh.servlet;import java.awt.Font;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.jfree.chart.ChartFactory;import org.jfree.chart.JFreeChart;import org.jfree.chart.plot.PiePlot;import org.jfree.chart.servlet.ServletUtilities;import org.jfree.chart.title.TextTitle;import org.jfree.data.general.DefaultPieDataset;public class jcPie extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doPost(request,response);}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {//设置 饼图默认的数据集 DefaultPieDataset dataset=new DefaultPieDataset();dataset.setValue("古典名著", 0.3);dataset.setValue("青春校园", 0.1);dataset.setValue("儿童读物", 0.3);dataset.setValue("异国风情", 0.1);dataset.setValue("报刊杂志", 0.2);JFreeChart chart=ChartFactory.createPieChart3D("图书销量", dataset, true, true, false);PiePlot pieplot=(PiePlot) chart.getPlot();//定义一个饼图对象pieplot.setLabelFont(new Font("宋体",0,12));TextTitle txtTitle=null;txtTitle=chart.getTitle();Font font=new Font("宋体",Font.BOLD,16);txtTitle.setFont(font);chart.getLegend().setItemFont(font);//表示在web服务器 临时目录中生成一个图片String filename=ServletUtilities.saveChartAsPNG(chart, 450, 300, null,request.getSession());String graphURL=request.getContextPath()+"/DisplayChart?filename="+filename;System.out.println(graphURL);request.setAttribute("imgURL", graphURL);this.getServletContext().getRequestDispatcher("/pie.jsp").forward(request, response);}}4.index.jsp 做请求 到jfpie servlet 然后转发到 pie.jsp
index.jsp
<body onload="window.location.href='${pageContext.request.contextPath}/servlet/jcPie'"> </body>pie.jsp
<body> <img alt="JfreeChart的简略应用" src="${imgURL}"> </body>5.访问 http://localhost:8083/JfreeChart/