<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="servlet.mapper.Account">
<select id="getlogin" resultType="Account_and_Password_class">
select * from
account
where useraccount = #{uname}
and password = #{pwd}
</select>
</mapper>
package servlet.mapper;
import org.apache.ibatis.annotations.Param;
import servlet.pojo.Account_and_Password_class;
import servlet.pojo.Email_and_Password_class;
import servlet.pojo.testdemo1;
import java.util.List;
public interface Account {
//用户注册
List<Account_and_Password_class> getlogin(@Param("uname")String uname,@Param("pwd")String pwd);
}
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<typeAliases>
<package name="servlet.pojo"/>
</typeAliases>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC"/>
<dataSource type="POOLED">
<!--数据库连接信息-->
<property name="driver" value="com.mysql.cj.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/java_web"/>
<property name="username" value="root"/>
<property name="password" value="123456"/>
</dataSource>
</environment>
</environments>
<mappers>
<!--加载sql映射文件-->
<!--<mapper resource="servlet/mapper/userMapper.xml"/>--><!--不用这样写直接用包扫描-->
<package name="servlet.mapper"/>
</mappers>
</configuration>
public class Login_rigister {
public static void main(String[] args) throws IOException {
//1.加载mybatis的核心配置文件,获取SqlSessionFactory
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
//2.获取SqlSession对象,用它来执行sql(可以在这里设置自动提交事务)
SqlSession sqlSession = sqlSessionFactory.openSession(true);
//3.获取UserMapper接口的代理对象
Account account = sqlSession.getMapper(Account.class);
List qqqq = account.getlogin("qqqq", "1234");
System.out.println(qqqq);
}
}
我的数据库确实有值,但是输出的是[null]