mybatis学习：mybatis的注解开发CRUD操作

Dao层：

 public interface IUserDao {

     /**
      * 查询所有结果
      * @return
      */
     @Select("select * from user")
     List<User> findAll();

     /**
      * 保存用户
      * @param user
      */
     @Insert("insert into user(username,address,sex,birthday) values(#{username},#{address},#{sex},#{birthday})")
     void saveUser(User user);

     /**
      * 更新用户
      * @param user
      */
     @Update("update user set username = #{username},address = #{address},sex = #{sex},birthday = #{birthday} where id = #{id}")
     void updateUser(User user);

     /**
      * 删除用户
      * @param id
      */
     @Delete("delete from user where id = #{id}")
     void deleteUser(Integer id);

     /**
      * 根据id查询用户
      * @param userId
      * @return
      */
     @Select("select * from user where id = #{id}")
     User findById(Integer userId);

     /**
      * 根据用户模糊查询
      * @param username
      * @return
      */
 //    @Select("select * from user where username like #{username}")     //参数占位符
     @Select("select * from user where username like '%${value}%'")      //字符串拼接
     List<User> findUserByName(String username);

     /**
      * 查询总用户数量
      * @return
      */
     @Select("select count(*) from user")
     int findTotalUser();

 }

test：

 public class AnnotationCRUDTest {

     private InputStream in;
     private SqlSessionFactory factory;
     private SqlSession session;
     private IUserDao userDao;

     @Before
     public void init() throws IOException {
         in = Resources.getResourceAsStream("SqlMapConfig.xml");
         factory = new SqlSessionFactoryBuilder().build(in);
         session = factory.openSession();
         userDao = session.getMapper(IUserDao.class);
     }

     @After
     public  void  destory() throws IOException {
         session.commit();
         session.close();
         in.close();
     }

     @Test
     public  void testSave(){
         User user = new User();
         user.setUsername("flypig");
         user.setAddress("中国");

         userDao.saveUser(user);
     }

     @Test
     public void testUpdate(){
         User user = new User();
         user.setId(49);
         user.setUsername("flypighhh");
         user.setAddress("China");
         user.setSex("男");
         user.setBirthday(new Date());

         userDao.updateUser(user);
     }

     @Test
     public void testDelete(){
         userDao.deleteUser(49);
     }

     @Test
     public void testFindOne(){
         User user = userDao.findById(48);
         System.out.println(user);
     }

     @Test
     public void testFindUserByName(){
         //List<User> users = userDao.findUserByName("%王%");
         List<User> users = userDao.findUserByName("王");
         for (User user : users) {
             System.out.println(user);
         }
     }

     @Test
     public void testFindTotal(){
         int total = userDao.findTotalUser();
         System.out.println(total);
     }

 }

解决实体类属性和数据库表字段不对应：

@Results(id="userMap",value={
             @Result(id=true,column = "id",property = "userId"),
             @Result(column = "username",property = "userName"),
             @Result(column = "address",property = "userAddress"),
             @Result(column = "sex",property = "userSex"),
             @Result(column = "birthday",property = "userBirthday"),
})    

//其他可根据id调用
@ResultMap(value={"userMap"})
//@ResultMap("userMap")