Mybatis的

之前在介绍CONCAT的用法时，入参采用的是一实体类封装形式，故parameterType参数类型是实体类，而这个则采用的是一个具体类型的参数，这时在我们判断mappper.xml中判断参数时，由于parameterType参数类型不是实体类了，判断参数时,这时就需要用_parameter来代替参数判断，如果直接采用入参的字段（如<if test="jkmc != null and jkmc != ''">）去判断则会报错

@RequestMapping(value = "/findEsbInterfaceByJkmcOrJkbhOrPyjp",produces = "application/json; charset=utf-8",method = RequestMethod.POST) public Result findEsbInterfaceByJkmcOrJkbhOrPyjp(@RequestParam(name = "jkmc",required=false) String jkmc) throws Exception{ return esbInterfaceService.findEsbInterfaceByJkmcOrJkbhOrPyjp(jkmc); }

---

<!--根据接口名称或接口编号或拼音简拼查询jkzt=1(正常)的接口列表--> <select id="findEsbInterfaceByJkmcOrJkbhOrPyjp" parameterType="java.lang.String" resultMap="BaseResultMap"> select <include refid="Base_Column_List" /> from ESB_INTERFACE <where> JKZT = '1' <if test="_parameter != null and _parameter != ''"> and CONCAT(CONCAT(CONCAT('',jkmc),jkbh),pyjp) like '%' || #{jkmc,jdbcType=VARCHAR} || '%' </if> </where> </select>