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{
width: 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……