mybatis基础配置

我这个写的比较简略，是自己短时间记录的可能只适合自己看，新手或者不懂的建议看看下面大神这篇：

https://www.cnblogs.com/homejim/p/9613205.html

1.MyBatis基础配置文件：mybatis_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>
  <environments default="development">
    <environment id="development">
      <transactionManager type="JDBC">
        <property name="" value=""/>
      </transactionManager>
      <dataSource type="UNPOOLED">
        <property name="driver" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/mybatis"/>
        <property name="username" value="root"/>
        <property name="password" value="root"/>
      </dataSource>
    </environment>
  </environments>

  <mappers>
    <mapper resource="com/learn/mybatis/role.xml"/>
  </mappers>
</configuration>

2.映射文件Role.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">
<mapper namespace="com.learn.mybatis.mapper.RoleMapper">
  <select id="getRole" parameterType="long" resultType="com.learn.mybatis.model.Role">
      select roleName form t_role where id=#{id} 
  </select>
</mapper>

3.定义一个调用接口RoleMapper.java

public interface RoleMapper{
    public Role getRole(Long id);
}

4.建立SqlSessionFactory：MyBatisUtil.java

public class MyBatisUtil {
    public static SqlSessionFactory getSqlSessionFactory() {
        // 通过配置文件获取数据库连接信息
        Reader reader = Resources.getResourceAsReader("com/learn/mybatis/mybatis_config.xml");
        // 通过配置信息构建一个SqlSessionFactory
        SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(reader);
        return sqlSessionFactory;
    }
}

5.实现按id查找姓名功能：test.java

public class test {
    public static void main(String[] args) {
        // 通过sqlSessionFactory打开一个数据库会话
        SqlSession sqlSession = MyBatisUtil.getSqlSessionFactory.openSession();
        RoleMapper roleMapper = sqlSession.getMapper(RoleMapper.class);
        Role role = roleMapper.getRole(1L);
　　　　　
        System.out.println("role_name->" + role.getRoleName());
        sqlSession.close();
    }
}

这样便完成了mybatis一个完整流程操作。

每天进步一点，积少以成多。