Javaweb+Mysql 用户管理系统项目（二 登录）
实现登陆功能
userlogin.jsp
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>用户登录界面</title>
<script type="text/javascript">
function changeCode(){
//获取验证码元素
var checkcode = document.getElementById("checkcode");
checkcode.src="CodeServlet?time="+new Date().getTime();
}
</script>
</head>
<body>
<form action="UserLoginServlet" method="post">
<table align="center" border="1" style="border-collapse:collapse;">
<tr>
<td colspan="4" align="center">用户登录</td>
</tr>
<tr height="40px">
<td>用户账户：</td>
<td colspan="3"><input type="text" name="userAccount" size="20" align="left"></td>
</tr>
<tr height="40px">
<td >用户密码：</td>
<td colspan="3"><input type="password" name="userPassword" size="20" align="left"></td>
</tr>
<!-- </table>
<table align="center"> -->
<tr height="40px">
<td>验证码：</td>
<!-- <td><input type="text" name="code" size="3" align="left"></td>
<td><a href="#" onclick="changeCode()">换一换</a></td>
<td><img id=checkcode alt="验证码" src="CodeServlet" onclick="changeCode()"/></td>
-->
<td colspan="3">
<input type="text" name="code" size="3" align="left">
<a href="#" onclick="changeCode()">换一换</a>
<img id=checkcode alt="验证码" src="CodeServlet" onclick="changeCode()"/>
</td>
</tr>
<!-- </table>
<table align="center"> -->
<tr>
<td colspan="4" align="center">
<input type="submit" value="登录">
<input type="button" value="注册"
onclick="window.location.href='userregister.jsp'">
<input type="button" value="恢复账号"
onclick="window.location.href='UserRecoverServlet'">
<a href="RecoverPWDServlet"><font >忘记密码？</font></a>
</td>
</tr>
</table>
<table align="center">
<tr>
<td align="center"><font color="RED">
<%
String UDmsg = (String) request.getAttribute("UDmsg");
String usermsg = (String) request.getAttribute("usermsg");
String codemsg = (String) request.getAttribute("codemsg");
if(UDmsg != null){
out.println(UDmsg);
}else if(usermsg != null){
out.println(usermsg);
}else if(codemsg != null){
out.println(codemsg);
}
%>
</font></td>
</tr>
</table>
<br>
</form>
</body>
</html>
Userdao数据库操作
/**
* 判断用户密码是否正确
*/
public User judgeUserPassword(String userAccount,String userPassword) {
Connection conn = null;
PreparedStatement ps = null;
ResultSet rs = null;
User user = null;
try {
conn=DBUtils.getConnection();
String sql="select * from users where user_account=? and user_password=?";
ps=conn.prepareStatement(sql);
ps.setString(1, userAccount);
ps.setString(2, userPassword);
rs=ps.executeQuery();
while(rs.next()) {
user = new User();
user.setUserId(rs.getInt("user_id"));
user.setUserName(rs.getString("user_name"));
user.setUserAccount(rs.getString("user_account"));
user.setUserPassword(rs.getString("user_password"));
user.setUserDisplay(rs.getString("user_display"));
user.setUserDeleteTime(rs.getString("user_deleteTime"));
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally {
DBUtils.closeAll(rs, ps, conn);
}
return user;
}
LoginServlet
package com.bin.action;
import java.io.IOException;
import java.util.ArrayList;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import javax.xml.ws.soap.AddressingFeature.Responses;
import com.bin.dao.UserDao;
import com.bin.entity.User;
/**
* Servlet implementation class UserLoginServlet
*/
public class UserLoginServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
public UserLoginServlet() {
super();
// TODO Auto-generated constructor stub
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
}
/**
* @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;charset=ust-8");
response.setHeader("pragma", "no-cache");
response.setHeader("cache-control", "no-cache");
response.setDateHeader("expires", 0);
HttpSession session=request.getSession();
//获取用户表单数据
String userAccount=request.getParameter("userAccount");
String userPassword=request.getParameter("userPassword");
String code=request.getParameter("code");
String scode=(String) session.getAttribute("scode");
//实例化
UserDao ud=new UserDao();
User user=null;
String userDisplay = ud.judgeUserDisplay(userAccount);
//用户登录验证处理
if(userDisplay == null){
String UDmsg = "很抱歉，用户不存在！您或许需要重新注册，谢谢！";
request.setAttribute("UDmsg", UDmsg);
request.getRequestDispatcher("userlogin.jsp").forward(request ,response);
}else if(userDisplay.equals("off")){
String UDmsg = "很抱歉，用户已被删除！您或许需要找回，谢谢！";
request.setAttribute("UDmsg", UDmsg);
request.getRequestDispatcher("userlogin.jsp").forward(request ,response);
}else if((user=ud.judgeUserPassword(userAccount,userPassword))==null){
String usermsg = "用户名或密码错误，请确认！";
request.setAttribute("usermsg", usermsg);
request.getRequestDispatcher("userlogin.jsp").forward(request ,response);
}else if(!code.equalsIgnoreCase(scode)){
String codemsg = "验证码错误，请确认！";
request.setAttribute("codemsg", codemsg);
request.getRequestDispatcher("userlogin.jsp").forward(request ,response);
}else if(user != null){//如果账号密码正确，跳转到用户管理界面
//向session中添加user对象
String userAccount2 = user.getUserAccount();
session.setAttribute("userAccount", userAccount2);
session.setAttribute("user", user);
//获取用户列表
ArrayList<User> list = ud.selectNotArrayList();
request.setAttribute("list", list);
//转发到用户管理界面
request.getRequestDispatcher("userlist.jsp").forward(request ,response);
//String path1 = resp.encodeURL(req.getContextPath()+"/userlist.jsp");
//resp.setHeader("refresh", "1;url="+path1);
//resp.sendRedirect(path1);
}
}
}