JSP网络开发逐步深入源代码

package servlet; import java.awt.Font; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.PrintWriter; import java.sql.ResultSet; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import org.jfree.chart.ChartFactory; import org.jfree.chart.ChartUtilities; import org.jfree.chart.JFreeChart; import org.jfree.chart.axis.CategoryAxis; import org.jfree.chart.axis.NumberAxis; import org.jfree.chart.axis.NumberTickUnit; import org.jfree.chart.plot.CategoryPlot; import org.jfree.chart.plot.PlotOrientation; import org.jfree.chart.title.TextTitle; import org.jfree.data.category.DefaultCategoryDataset; import bean.Indagate; import bean.OperateDb; public class Servlet2 extends HttpServlet { private static final long serialVersionUID = 1L; OperateDb operatedb; Indagate indagate; ResultSet rs; HttpSession session; /** * The doGet method of the servlet. <br> * * This method is called when a form has its tag value method equals to get. * * @param request * the request send by the client to the server * @param response * the response send by the server to the client * @throws ServletException * if an error occurred * @throws IOException * if an error occurred */ public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // 实例化对象 operatedb = new OperateDb(); indagate = new Indagate(); session = request.getSession(); response.setContentType("text/html;charset=utf-8"); PrintWriter out = response.getWriter(); // 数据库中读取调查第一个问题的数据 String sql = "select * from indagate where id = 2"; rs = operatedb.query(sql); try { if (rs.next()) { // 将查询结果封装到indagate中 indagate.setId(rs.getInt(1)); indagate.setTitle(rs.getString(2)); indagate.setFirsta(rs.getString(3)); indagate.setFirstv(rs.getInt(4)); indagate.setSeconda(rs.getString(5)); indagate.setSecondv(rs.getInt(6)); indagate.setThirda(rs.getString(7)); indagate.setThirdv(rs.getInt(8)); indagate.setFourtha(rs.getString(9)); indagate.setFourthv(rs.getInt(10)); indagate.setTotal(rs.getInt(11)); } } catch (Exception e) { System.out.println("数据读取错误！"); e.printStackTrace(); } // 判断用户选择选项 String radio = request.getParameter("radio2"); if (radio.equals("radio")) { indagate.setFirstv(indagate.getFirstv() + 1); } if (radio.equals("radio2")) { indagate.setSecondv(indagate.getSecondv() + 1); } if (radio.equals("radio3")) { indagate.setThirdv(indagate.getThirdv() + 1); } if (radio.equals("radio4")) { indagate.setFourthv(indagate.getFourthv() + 1); } indagate.setTotal(indagate.getTotal() + 1); // 在session中保存调查题目 session.setAttribute("question", indagate.getTitle()); // 更新数据库中的数据 operatedb.update(indagate); // 关闭数据库链接 operatedb.close(); // 创建柱状图的数据集，从indagate中调用 DefaultCategoryDataset dataset = new DefaultCategoryDataset(); dataset.setValue(indagate.getFirstv(), indagate.getFirsta(), indagate .getFirsta()); dataset.setValue(indagate.getSecondv(), indagate.getSeconda(), indagate .getSeconda()); dataset.setValue(indagate.getThirdv(), indagate.getThirda(), indagate .getThirda()); dataset.setValue(indagate.getFourthv(), indagate.getFourtha(), indagate .getFourtha()); // 使用工厂创建饼图图形对象 Integer i = new Integer(indagate.getTotal()); JFreeChart chart = ChartFactory.createBarChart3D("问题："+indagate.getTitle(), "回答过此问题的总人数是：" + i.toString() + "人", "人 数", dataset, PlotOrientation.VERTICAL, true, false, false); // 设置图形标题、标签字体，防止乱码出现 TextTitle txtTitle = chart.getTitle(); txtTitle.setFont(new Font("黑体", 10, 20)); CategoryPlot categoryplot = (CategoryPlot) chart.getCategoryPlot(); CategoryAxis domainAxis = categoryplot.getDomainAxis(); NumberAxis numberaxis = (NumberAxis) categoryplot.getRangeAxis(); domainAxis.setTickLabelFont(new Font("宋体", 5, 11)); domainAxis.setLabelFont(new Font("宋体", 5, 12)); numberaxis.setTickLabelFont(new Font("宋体", 5, 12)); numberaxis.setLabelFont(new Font("宋体", 5, 12)); chart.getLegend().setItemFont(new Font("黑体", 5, 14)); //设置纵坐标刻度单位 numberaxis.setTickUnit(new NumberTickUnit(3D)); // 保存图形到指定目录 File file = new File("..\\webapps\\indagate\\images\\indagate.jpg"); FileOutputStream jpgchart = new FileOutputStream(file); ChartUtilities.writeChartAsJPEG(jpgchart, chart, 600, 400); // 转向到结果显示页面 response.sendRedirect("../result.jsp"); out.flush(); out.close(); } /** * The doPost method of the servlet. <br> * * This method is called when a form has its tag value method equals to * post. * * @param request * the request send by the client to the server * @param response * the response send by the server to the client * @throws ServletException * if an error occurred * @throws IOException * if an error occurred */ public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }