package user.web.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import cn.itcast.commons.CommonUtils;
import user.domain.User;
import user.service.UserException;
import user.service.UserService;
public class LoginServlet extends HttpServlet {
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
response.setContentType("text/html;charset=utf-8");
// 依赖UserService
UserService userService = new UserService();
/*
* 1、封装表单数据到User form中
* 2、调用service的login()方法，得到返回的User user对象
* > 如果抛出异常：获取异常信息，保存到request域，再保存form，转发到login.jsp
* > 如果没有异常，保存返回值到session中，重定向到welcome.jsp
*/
User form = CommonUtils.toBean(request.getParameterMap(), User.class);
try {
UserService us = new UserService();
User user = us.login(form);
request.getSession().setAttribute("sessionUser", user);
response.sendRedirect(request.getContextPath()+"/user/welcome.jsp");
} catch (UserException e) {
request.setAttribute("msg", e.getMessage());
request.setAttribute("user", form);
request.getRequestDispatcher("/user/login.jsp").forward(request, response);
}
}
}
LoginServlet
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'login.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<h1>登录</h1>
<p style="color: red; font-weight: 900">${msg }</p>
<form action="<c:url value='/LoginServlet'/>" method="post">
用户名：<input type="text" name="username" value="${user.username }" /><br/>
密 码：<input type="password" name="password" value="${user.password }"/><br/>
<input type="submit" value="登录"/>
</form>
</body>
</html>
login.jsp
