Mybatis框架搭建-蒲公英云

Mybatis框架搭建

小灰灰 2020-11-26 10:19 885阅读 0赞

1、dynamicProject工程结构

2、全局配置文件mybais-config.xml

<?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> <properties resource="db.properties"></properties> <!-- 为User实体类设置别名 --> <typeAliases > <typeAlias type="com.jie.mybatis.entity.User" alias="User"/> </typeAliases> <!-- 和spring整合后将去除environments配置 --> <environments default="development"> <environment id="development"> <!-- 使用jdbc事务管理，由mybatis管理 --> <transactionManager type="jdbc"></transactionManager> <!-- 数据库连接池，由mybatis管理 --> <dataSource type="POOLED"> <property name="driver" value="${driver}" /> <property name="url" value="${url}" /> <property name="username" value="${username}" /> <property name="password" value="${password}" /> </dataSource> </environment> </environments> <!-- 配置映射文件 --> <mappers> <mapper resource="com/jie/mybatis/mapper/userMapper.xml" /> </mappers> </configuration>

3 、映射文件mapper.xml

<?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">
  <!-- 命名空间指向dao接口 -->
<mapper namespace="com.jie.mybatis.dao.UserDao">
    <!-- id对应dao接口中方法的名字， parameterType指输入类型，resultType是输出类型，
    正常是实体类对象，通过设置别名后不用写报名加类名-->
    <select id="findUserById" parameterType="int" resultType="User">
        select * from userInfo where userId = #{id}
    </select>
</mapper>

4、测试类

public class MybatisTest {
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        try {
            test1();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    public static void test1() throws IOException {
        // 加载配置文件得到sqlsessionFactory工厂
        // 构建sqlSessionFactor
        String resource = "mybatis-config.xml";
        InputStream inputStream = Resources.getResourceAsStream(resource);
        SqlSessionFactory sessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        // 通过工厂得到SqlSession
        SqlSession session = sessionFactory.openSession();
        UserDao userDao = session.getMapper(UserDao.class);
        User user = userDao.findUserById(1);
        System.out.println(user);
    }
}