servlet+jsp+java实现Web应用
环境：
1，eclipse
2，tomcat
3，eclipse tomcat 插件
开发过程：
1，建立一个Dynamic Web Project
2，创建一个欢迎页面
页面可以是jsp/html，我们选择一个jsp页面（放在WebContent内）
<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>Insert title here</title> </head> <body> <h1>Do you come in?</h1> <form method="post" action="hello.do"> Select:<br> <select> <option>yes <option>no </select> <center> <input type="submit"> </center> </form> </body> </html>
3，向工程添加一个servlet文件
package com.example; 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; /** * Servlet implementation class Welcome */ @WebServlet("/Welcome") public class Welcome extends HttpServlet { private static final long serialVersionUID = 1L; /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub response.setContentType("text/html"); PrintWriter out = response.getWriter(); String c = request.getParameter("select"); if(c.equals("yes")) out.print("Welcome!"); else out.print("I don't like you!"); //带参跳到另一个页面 request.setAttribute("token", token); request.getRequestDispatcher("welcome.jsp").forward(request,response); } }
4，创建welcome.jsp页面，并接受参数值
<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> <title>Insert title here</title> <% String token = request.getParameter("token");//用request得到 %> <style> #ifr_fr{ 84%; height: 700px; } </style> </head> <body > welcome to rzzx1. <iframe id="ifr_fr" name="ifr_fr" frameborder="0" src=""></iframe> </body> </html>
5，创建一个web.xml
web.xml用来建立servlet与jsp的关系（需要放在WEB-INF内）。
根据不同的url来调用不同的servlet来进行处理。
<?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" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5">
<display-name></display-name>
<servlet>
<servlet-name>Welcome</servlet-name>//要与下面的名称相同
<servlet-class>com.example.Welcome</servlet-class>//调用的类的位置
</servlet>
<servlet-mapping>
<servlet-name>Welcome</servlet-name>
<url-pattern>/hello.do</url-pattern>//url标识
</servlet-mapping>
</web-app>
6，测试地址：http://localhost:8080/webtest/hello.do
7，可能会提示：HTTP method GET is not supported by this URL
解决方案：
public void doPost(HttpServletR…… 改成： public void service(HttpServletR……