mybatis0070- 一次简单查询的执行过程

一次简单查询

public class Test {
    public static void main(String[] args) {
        try {
            String resource = "mybatis.xml";
            InputStream inputStream = Resources.getResourceAsStream(resource);
            SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
            SqlSession sqlSession = sqlSessionFactory.openSession();
            SysRoleMapper sysRoleMapper = sqlSession.getMapper(SysRoleMapper.class);
            SysRole sysRole = sysRoleMapper.selectById(1);
            System.out.println(sysRole);
            sqlSession.close();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
        }
    }
}

上述过程可以分为下面几个步骤

1. 解析xml配置文件，生成SqlSessionFactory

2. 通过SqlSessionFactory创建sqlSession

3. Mapper接口到SqlSession的跨越

4. SqlSeesion执行sql语句