===============
MyBatis单元测试
===============

在pom.xml中添加JUnit依赖：

<!-- JUnit -->
<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.13.2</version>
    <scope>test</scope>
</dependency>

在StudentDao类名后面点右键
    生成...
        测试...
            勾选需要被测试的方法

public class StudentDaoTest {
    // 测试增加学生
    @Test
    public void testAdd() {
    }

    // 测试删除学生
    @Test
    public void testDel() {
    }
}

测试增加学生：

public class StudentDaoTest {
    ...
    // 测试增加学生
    @Test
    public void testAdd() {
        // SQL会话工厂建造器
        SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();

        try {
            // MyBatis配置文件输入流
            InputStream is = Resources.getResourceAsStream("mybatis-config.xml");
            // SQL会话工厂
            SqlSessionFactory factory = builder.build(is);
            // SQL会话
            SqlSession session = factory.openSession();
            // 数据访问对象
            StudentDao dao = session.getMapper(StudentDao.class);

            // 学生实体
            Student student = new Student(0, "1001", "张飞", "男", 21);
            // 增加学生
            int rows = dao.add(student);
            // 打印受影响的行数
            System.out.println(rows);
            // 提交事务
            session.commit();
        }
        catch (IOException e) {
            e.printStackTrace();
        }
    }
    ...
}

例程：HelloMyBatis

 ___________________________________
|        mybatis-config.xml         |
|-----------------------------------|
|MySQL：driver/url/username/password|
|  _______________________________  |
| |       StudentMapper.xml       | |
| |-------------------------------| |
| |          /add：insert into ...| |
| |StudentDao                     | |
| |          \del：delete from ...| |
| |_______________________________| |
|___________________________________|
                  |
                  v
             InputStream
                  |
                  v
       SqlSessionFactoryBuilder
                  |
                  v
          SqlSessionFactory
                  |
                  v
             SqlSession
                  |
                  v
 ___________________________________
|    StudentDao接口的实现类对象     |
|-----------------------------------|
|                  /add { ... }     |
|    StudentDaoImpl                 |
|                  \del { ... }     |
|___________________________________|