用Spring MVC和MyBatis实现登录和注册功能的代码示例

以下是用Spring MVC和MyBatis实现登录和注册功能的示例代码：

1. 配置web.xml

<web-app>
  <display-name>SpringMVC+MyBatis Demo</display-name>
  <servlet>
    <servlet-name>SpringMVC</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>/WEB-INF/springmvc-config.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  
  <servlet-mapping>
    <servlet-name>SpringMVC</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
  
  <welcome-file-list>
    <welcome-file>/index.jsp</welcome-file>
  </welcome-file-list>
</web-app>

2. 配置springmvc-config.xml

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:p="http://www.springframework.org/schema/p"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
    http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
    http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd">
 
    <context:component-scan base-package="com.example.controller" />
    
    <mvc:annotation-driven />
 
    <bean id="viewResolver"
         class="org.springframework.web.servlet.view.InternalResourceViewResolver"
         p:prefix="/WEB-INF/views/"
         p:suffix=".jsp" />
</beans>

3. 配置数据库连接

<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
    <property name="driverClassName" value="com.mysql.jdbc.Driver" />
    <property name="url" value="jdbc:mysql://localhost:3306/test" />
    <property name="username" value="root" />
    <property name="password" value="123456" />
</bean>
 
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
    <property name="dataSource" ref="dataSource" />
    <property name="configLocation" value="classpath:mybatis-config.xml" />
</bean>
 
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
    <property name="basePackage" value="com.example.mapper" />
</bean>

4. 编写Mapper接口和Mapper映射文件

UserMapper.java

public interface UserMapper {
    User getUserByName(String name);
    void addUser(User user);
}

UserMapper.xml

<mapper namespace="com.example.mapper.UserMapper">
    <select id="getUserByName" parameterType="java.lang.String" resultType="com.example.model.User">
        SELECT * FROM user WHERE name=#{name}
    </select>
    <insert id="addUser" parameterType="com.example.model.User">
        INSERT INTO user(name, password) VALUES(#{name}, #{password})
    </insert>
</mapper>

5. 编写Controller

@Controller
public class UserController {
    @Autowired
    private UserMapper userMapper;
 
    @RequestMapping(value="/login", method=RequestMethod.POST)
    public ModelAndView login(@RequestParam("name") String name, 
                              @RequestParam("password") String password) {
        User user = userMapper.getUserByName(name);
        if(user != null && user.getPassword().equals(password)) {
            return new ModelAndView("success");
        } else {
            return new ModelAndView("error");
        }
    }
 
    @RequestMapping(value="/register", method=RequestMethod.POST)
    public ModelAndView register(@RequestParam("name") String name, 
                                 @RequestParam("password") String password) {
        User user = userMapper.getUserByName(name);
        if(user != null) {
            return new ModelAndView("error");
        } else {
            user = new User();
            user.setName(name);
            user.setPassword(password);
            userMapper.addUser(user);
            return new ModelAndView("success");
        }
    }
}

6. 编写JSP页面

login.jsp

<form action="login" method="post">
    <label for="name">Name:</label>
    <input type="text" id="name" name="name"><br><br>
    <label for="password">Password:</label>
    <input type="password" id="password" name="password"><br><br>
    <input type="submit" value="Submit">
</form>

register.jsp

<form action="register" method="post">
    <label for="name">Name:</label>
    <input type="text" id="name" name="name"><br><br>
    <label for="password">Password:</label>
    <input type="password" id="password" name="password"><br><br>
    <input type="submit" value="Submit">
</form>

success.jsp

<h2>Success!</h2>

error.jsp

<h2>Error!</h2>

以上就是用Spring MVC和MyBatis实现登录和注册功能的示例代码。