MyBatis的注解

基于注解的mybatis和spring整合:http://huangmin001.iteye.com/blog/1185806
这个文章说的很详细,很值得一看.


Mapper中注解（Annotation）的使用示例:http://puras.cn/mybatis-annotation-example

Mapper：

public interface RoleMapper {
    final String SELECT_ALL = "SELECT * FROM nap_roles";
    final String SELECT_BY_ID = "SELECT * FROM nap_roles WHERE id=#{id}";
    final String INSERT = "INSERT INTO nap_roles(name, description, ctime, mtime) VALUES(#{name}, #{description}, #{creationTime}, #{modifiedTime})";
    final String UPDATE = "UPDATE nap_roles SET name=#{name}, description=#{description}, mtime=#{modifiedTime} WHERE id=#{id}";
    final String DELETE = "DELETE FROM nap_roles WHERE id=#{id}";
    final String SELECT_BY_PAGE_BEGIN = "SELECT * FROM nap_roles";
    final String SELECT_BY_PAGE_END = " limit #{startPosition}, #{maxResult}";
    final String COUNT = "SELECT COUNT(id) FROM nap_roles WHERE 1=1 ";

    @Insert(INSERT)
    @Options(useGeneratedKeys = true, keyProperty = "id")
    void create(Role role);

    @Update(UPDATE)
    void update(Role role);

    @Delete(DELETE)
    void delete(Long id);

    @Select(SELECT_ALL)
    @Results(value = {
            @Result(property="id"),
            @Result(property="name"),
            @Result(property="description"),
            @Result(property="creationTime", column="ctime"),
            @Result(property="modifiedTime", column="mtime")
    })
    List findAll();

    @SelectProvider(type = RoleProvider.class, method = "findByPage")
    @Results(value = {
            @Result(property="id"),
            @Result(property="name"),
            @Result(property="description"),
            @Result(property="creationTime", column="ctime"),
            @Result(property="modifiedTime", column="mtime")
    })
    List findByPage(Map params);

    @Select(SELECT_BY_ID)
    @Results(value = {
            @Result(property="id"),
            @Result(property="name"),
            @Result(property="description"),
            @Result(property="creationTime", column="ctime"),
            @Result(property="modifiedTime", column="mtime")
    })
    Role findById(Long id);

    @SelectProvider(type = RoleProvider.class, method = "getCount")
    int getCount(Role role);

    @Select(COUNT)
    int count();
}

在使用比较复杂的SQL时，会用到各种Provider来处理。

虽然都改用Annotation了，但还有些地方不是特别的爽。

1、ResultMap，不知道怎么来定义一个对象，所有的都引用一个；

2、所有的SQL都写到JAVA里了，修改起来，也是件麻烦事。