创建input.jsp页面，通过表单输入学号、姓名后，单击登录按钮，控制转发到FirstServlet对其进行处理，然后通过请求对象的getRequestDispartcher()获得RequestDispartcher对象，将请求转发至SecondServlet，在SecondServlet中用输出流对象out输出该学生的学号和姓名。输出页面还包含一个超链接，单击该链接可以返回至input.jsp页面。
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
login.jsp
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>ForwordJsp.jsp</title>
<meta http-equiv="description" content="This is my page" chartset="utf-8">
</head>
<body>
this is students form: <br>
<form action="FirstServlet.do" >
学号:<input name="id" value=" "><br><br>
姓名:<input name="name" value=" "><br><br>
<a> </a>
<button type="submit">登录</button>
<a> </a>
<button type="reset" >取消</button>
</form>
</body>
</html>
package com.demo;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.List;
import java.util.regex.Pattern;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@WebServlet("/getMethod")
public class SecondServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html;charset=utf-8");
PrintWriter out = response.getWriter();
Student stu = (Student) request.getAttribute("stu");
String id = stu.getId();
String name = stu.getName();
out.println("<!DOCTYPE>");
out.println("<HTML>");
out.println(" <HEAD><TITLE>result</TITLE></HEAD>");
out.println(" <BODY>");
out.print(" 学号: "+id + "<br> ");
out.print(" 姓名: "+name + "<br> ");
out.print("<div><a href=\"http://localhost:8080/demo/login.jsp\">返回输入首页 </a></div>");
out.println(" </BODY>");
out.println("</HTML>");
out.flush();
out.close();
}
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doGet(request, response);
}
}
package com.demo;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.Enumeration;
import java.util.List;
import javax.json.Json;
import javax.json.JsonArray;
import javax.json.JsonObject;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@WebServlet("/login")
public class FirstServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
String id = request.getParameter("id");
String name = request.getParameter("name");
request.setAttribute("stu",new Student(id, name));
System.out.println("成功 == "+ id +" == "+name);
request.getRequestDispatcher("/SecondServlet.do").forward(request, response);
out.flush();
out.close();
}
}
