本文实例为大家分享了用Spring框架实现用户登录的具体代码，供大家参考，具体内容如下
流程：用户登录需求
登录页面login.jsp>>输入用户名username和密码password，如果用户名和密码在数据库中能找到，则实现登录成功界面hello.jsp，不成功则跳转到失败页面error.jsp
1.创建项目架构
（1）创建Maven项目
Add Maven Property >> Name：archetypeCatalog >> value：internal
（2）添加本地数据仓库
（3）创建项目目录
1)groupId：指代公司名 >> com.zzx >> artifactId：指代项目名 >> spring_login
2)在项目根目录底下创建文件夹target；
3)在src >> main >> java 设置为Sources Root; src >> main >> resources 设置为Resources Root;
4)加载Pom.xml文件架包，一般此文件在实际研发中都是直接由架构师来完成的操作。一般需要注意架包版本的一致性，文件版本。
5)关于数据库设计：tb_user
uid（用户编号）,username（用户名）,password（用户密码）,tid（用户类型）。
resources >> db.properties
model、entity >> bean >> User
Spring核心配置文件applicationContext.xml
2.以下为具体代码：
Spring核心配置文件 applicationContext.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<!-- 1.加载db.properties取到有效参数 -->
<context:property-placeholder location="classpath:db.properties" />
<!-- 2.加载数据源 -->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="${driverClass}" /> <!-- EL表达式,JSTL -->
<property name="url" value="${url}" />
<property name="username" value="${user}" />
<property name="password" value="${password}" />
</bean>
<!-- 3.创建jdbcTemplate对象 -->
<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSource" />
</bean>
<!-- 4.开启注解作用 -->
<context:component-scan base-package="com.zzx" />
<bean id="userDao" class="com.zzx.dao.impl.UserDaoImpl" />
<bean id="userService" class="com.zzx.service.impl.UserServiceImpl" />
</beans>
连接数据库 db.properties
driverClass=com.mysql.jdbc.Driver
url=jdbc:mysql://127.0.0.1:3306/db_java1ssm?useSSL=true&characterEncoding=utf-8
user=root
password=123456
webapp下配置web.xml文件
<!DOCTYPE web-app PUBLIC
"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd" >
<web-app>
<display-name>Archetype Created Web Application</display-name>
<!-- 1.配置applicationContext.xml -->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath*:applicationContext.xml</param-value>
</context-param>
<!-- 2.监听器 -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
</web-app>
jsp页面
<%--login.jsp--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>用户登录</title>
</head>
<body>
<div id="content" align="center">
<h3>用户登录</h3>
<hr>
<form action="loginServlet.do" method="post">
<table border="1" cellpadding="0" cellspacing="0" width="300px">
<tr>
<td><label for="username">用户名:</label></td>
<td><input type="text" id="username" name="username"/></td>
</tr>
<tr>
<td><label for="password">用户密码:</label></td>
<td><input type="text" id="password" name="password"/></td>
</tr>
<tr>
<td colspan="2"> <input type="submit" name="submit" id="submit" value="登录"/></td>
</tr>
</table>
</form>
</div>
</body>
</html>
<%--hello.jsp--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" isELIgnored="false" %>
<html>
<head>
<title>登录成功页面</title>
</head>
<body>
<font>欢迎您，${user.username}</font>
</body>
</html>
<%--error.jsp--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" isELIgnored="false" %>
<html>
<head>
<title>登录失败页面</title>
</head>
<body>
<font>登录失败！请你重新登录！</font>
</body>
</html>
bean层User类
public class User {
private int uid;
private String username;
private String password;
private int tid;
public int getUid() {
return uid;
}
public void setUid(int uid) {
this.uid = uid;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public int getTid() {
return tid;
}
public void setTid(int tid) {
this.tid = tid;
}
public User() {
}
public User(int uid, String username, String password, int tid) {
this.uid = uid;
this.username = username;
this.password = password;
this.tid = tid;
}
public User(String username, String password, int tid) {
this.username = username;
this.password = password;
this.tid = tid;
}
@Override
public String toString() {
return "User{" +
"uid=" + uid +
", username='" + username + '\'' +
", password='" + password + '\'' +
", tid=" + tid +
'}';
}
}
dao层UserDao
@Component
public interface UserDao {
//用户登录
User doLogin(String username,String password);
}
UserDaoImpl
@Component
public class UserDaoImpl implements UserDao {
@Autowired
private JdbcTemplate jdbcTemplate;
public void setJdbcTemplate(JdbcTemplate jdbcTemplate) {
this.jdbcTemplate = jdbcTemplate;
}
@Override
public User doLogin(String username, String password) {
String sql = "select * from tb_user where username=? and password=?";
BeanPropertyRowMapper<User> mapper = new BeanPropertyRowMapper<>(User.class);
User user = null;
user = jdbcTemplate.queryForObject(sql, mapper, username, password);
return user;
}
}
service层UserService
@Service
public interface UserService {
//用户登录
User doLogin(String username, String password);
}
UserServiceImpl
@Service
public class UserServiceImpl implements UserService {
@Autowired
private UserDao userDao ;
public void setUserDao(UserDao userDao) {
this.userDao = userDao;
}
@Override
public User doLogin(String username, String password) {
return userDao.doLogin(username,password);
}
}
LoginServlet
@WebServlet("*.do")
public class LoginServlet extends javax.servlet.http.HttpServlet {
private static final long serialVersionUID =1L;
// 报错是因为这个里面少tomcat - 加载tomcat
protected void doPost(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
// 中文乱码问题 : 国际标准化
request.setCharacterEncoding("utf-8");
response.setContentType("text/html;charset=UTF-8");
// applicationContext.xml
ApplicationContext ioc = WebApplicationContextUtils.getWebApplicationContext(getServletContext());
// 获取用户名
String username = request.getParameter("username");
String password = request.getParameter("password");
UserService userService = (UserService) ioc.getBean("userService");
User user = userService.doLogin(username, password);
request.setAttribute("user",user);
if(user==null){
// 失败
request.getRequestDispatcher("error.jsp").forward(request,response);
}else{
request.getRequestDispatcher("hello.jsp").forward(request,response);
}
}
protected void doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
this.doPost(request,response);
}
}
最后配置一下Tomcat服务器运行
下面是我的运行截图
