package com.mvc; import java.io.IOException; import javax.servlet.RequestDispatcher; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class example6_1 extends HttpServlet { /** * */ private static final long serialVersionUID = 1L; @Override public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub model data = new model();// 创建javabean对象 request.setAttribute("data", data); String shouxiang = request.getParameter("a"); int a = Integer.parseInt(shouxiang); data.setA(a); String xiangshu = request.getParameter("n"); int n = Integer.parseInt(xiangshu); data.setN(n); String gong = request.getParameter("q"); int q = Integer.parseInt(gong); data.setQ(q); data.setName("等差数列的公差"); int sum = 0; for (int i = 0; i < n; i++) { sum += a; a += q; } data.setsum(sum); RequestDispatcher dispatcher = request.getRequestDispatcher("show.jsp"); dispatcher.forward(request, response); } @Override public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub model data = new model();// 创建javabean对象 request.setCharacterEncoding("iso-8859-1"); request.setAttribute("data", data); String shouxiang = request.getParameter("a"); int a = Integer.parseInt(shouxiang); data.setA(a); String xiangshu = request.getParameter("n"); int n = Integer.parseInt(xiangshu); data.setN(n); String gong = request.getParameter("q"); int q = Integer.parseInt(gong); data.setQ(q); data.setName("等比数列的公差"); int sum = 1; for (int i = 0; i < n; i++) { sum += a; a *= q; } data.setsum(sum); RequestDispatcher dispatcher = request.getRequestDispatcher("show.jsp"); dispatcher.forward(request, response); } } package com.mvc; public class model { int a; int n; int q; int sum; String name = ""; public String getName() { return name; } public void setName(String name) { this.name = name; } public int getsum() { return sum; } public void setsum(int sum) { this.sum = sum; } public int getA() { return a; } public void setA(int a) { this.a = a; } public int getN() { return n; } public void setN(int n) { this.n = n; } public int getQ() { return q; } public void setQ(int q) { this.q = q; } } <?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0"> <servlet> <servlet-name>hhh</servlet-name> <servlet-class>com.mvc.example6_1</servlet-class> </servlet> <servlet-mapping> <servlet-name>hhh</servlet-name> <url-pattern>/heh</url-pattern> </servlet-mapping> </web-app> <%@ page contentType="text/html; charset=gb2312"%> <html> <head> <title>这是一个动态页面</title> </head> <body> <form action="show.jsp" method="get"> 等差数列求和:<br> 输入首项<input type="text" name="a"> 输入公差:<input type="text" name="q"> 求和项数:<input type="text" name="n"> <input type="submit" value="提交"> </form> <form action="heh" method="post"> 等比数列求和:<br> 输入首项<input type="text" name="a"> 输入公比:<input type="text" name="q"> 求和项数:<input type="text" name="n"> <input type="submit" value="提交"> </form> </body> </html> <%@ page contentType="text/html; charset=gb2312"%> <jsp:useBean id="data" class="com.mvc.model" scope="request"></jsp:useBean> <table border="1"> <tr> <th>数列的首项</th> <th><jsp:getProperty property="name" name="data" /></th> <th>所求项数</th> <th>求和结果</th> </tr> <tr> <td><jsp:getProperty property="a" name="data" /></td> <td><jsp:getProperty property="name" name="data" /></td> <td><jsp:getProperty property="n" name="data" /></td> <td><jsp:getProperty property="sum" name="data" /></td> </tr> </table>
一定要仔细检查每一个地方， 检查哪些最容易被忽略的地方。 例如包名是否与预留关键字冲突，web.xml位置是否正确。等