public interface OrderMapper extends SqlMapper{

@Select("select * from tbl_order where room like #{room} and mydate like #{mydate}")
public List<Order> getbyroom(OrderPara op);

}

这样整个语句是写死的，必须有2个参数，在这种模式下，如何能实现根据room和mydate是否为空来动态的拼写sql语句
比如当mydate=""

Select("select * from tbl_order where room like #{room} ")
public List<Order> getbyroom(OrderPara op);

如果用xml来配置语句的话，可以用

<when test="title != null">
and mydate= #{mydate}
</when>

如果是用@Select

这种 改如何做呢？

解决方案：

用script标签包围，然后像xml语法一样书写

@Select({"<script>",
    "SELECT * FROM tbl_order",
    "WHERE 1=1",
    "<when test='title!=null'>",
    "AND mydate = #{mydate}",
    "</when>",
    "</script>"})