实验内容

• 1.使用servlet接收前台表单数据，表单包括用户姓名、年龄、所在学校
• 2.用get和post两种方式传送到后台，用户姓名不允许为空
• 3.servlet1接收到数据以后，调用servlet2进行验证，如果验证年龄小于20，返回数据“欢迎你，少年”(利用forward和include来操作)
• 4.如果年龄大于40岁，页面跳转至一个jsp（使用send redirect ），显示 “欢迎您，老先生”

• 1.整体项目结构
• 2. 代码
• • 2.1 填写信息页面---index.jsp
  • 2.2 servlet1.java
  • 2.3 servlet2.java
  • 2.4 info.jsp
• 3. 运行
• 4.注意点

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>










	

		用户姓名：

		年龄：

		所在学校： 
			        		
		   
	

package com.szh.servlet;

import java.io.IOException;
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("/servlet1")
public class servlet1 extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    
    public servlet1() {
        super();
        // TODO Auto-generated constructor stub
    }

	
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		System.out.println("get请求将执行");
		
		String userName = request.getParameter("userName");
		//String userName = new String(request.getParameter("userName").getBytes("ISO-8859-1"),"utf-8");
		String userAge = request.getParameter("userAge");
		@SuppressWarnings("unused")
		String userSchool = request.getParameter("userSchool");
		
		response.setContentType("text/html;charset=utf-8");
		request.setAttribute("userName",userName );
		request.setAttribute("userAge",userAge );
		
		
		request.getRequestDispatcher("/servlet2").forward(request,response);//不是重定向，而是转发
	}

	
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		System.out.println("post请求将执行");
		doGet(request, response);
	}

}

package com.szh.servlet;

import java.io.IOException;
import java.io.PrintWriter;

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("/servlet2")
public class servlet2 extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    
    public servlet2() {
        super();
        // TODO Auto-generated constructor stub
    }

	
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		String userName = (String) request.getAttribute("userName");
		String userAge = (String) request.getAttribute("userAge");
		
		
		int age = Integer.parseInt(userAge);
		System.out.println(age);
		
		if(age < 20) 
		{	
			PrintWriter out = response.getWriter();
			out.print("欢迎你 ，少年"); 
		}
		if(age > 40)
		{
			request.getSession().setAttribute("name",userName );
			response.sendRedirect("/demo5YoungerAndOlder/info.jsp");//重定向
		}
	}
	

	
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doGet(request, response);
	}

}

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>







欢迎您，老先生
<%=request.getSession().getAttribute("name") %>

代码是正确的，唯一注意的地方是路径