Ibatis中的isNotNull、isEqual、isEmpty的区别

isNull判断property字段是否是null

isEmpty判断property字段 是否是null 和 空字符串

isEqual相当于equals，数字用得多些，一般都是判断状态值

转载自：http://jun1986.iteye.com/blog/1402191

例子1:(isEqual)

<isEqual property="state" compareValue="0">< /isEqual>
或
<isEqual property="state" compareProperty="nextState"></isEqual>

例子2：

传入的map或者类的属性name等于”1”吗，是就附加and和vvvv

<isEqual property="name" compareValue="1" prepend="and">
vvvv = '哈哈'
< /isEqual>

传入的map或者类的属性name是null吗，是就附加and和vvvv = null

< isNull property="name" prepend="and">
vvvv = null
< /isNull>

sqlmap

<select id="querySingleModelByOut"  parameterClass="com.hanpeng.base.phone.model.TBussinessNotice"
resultClass="com.hanpeng.base.phone.model.TBussinessNotice">
select * from (select row_.*, rownum rownum_ from (
SELECT
i.NOTICE_NUM  as noticeNum ,
i.BUSSINESS_ID  as bussinessId ,
i.STATE  as state ,
i.READ_DATE  as readDate ,
n.NOTICE_TITLE as noticeTitle ,
n.NOTICE_INFO as noticeInfo ,
n.CREATE_DATE as createDate ,
n.EMPLOYEE_ID as employeeId ,
n.NOTICE_TYPE as noticeType ,
n.NOTICE_SHOW_TYPE as noticeShowType ,
n.FINISH_DATE as finishDate ,
n.PUBLISH_DATE as publishDate
FROM  T_BUSSINESS_NOTICE i left join T_NOTICE n on n.NOTICE_NUM = i.NOTICE_NUM
WHERE
n.PUBLISH_DATE <= sysdate AND n.FINISH_DATE >= sysdate
<isNotEmpty prepend=" AND " property="bussinessId">
i.BUSSINESS_ID = #bussinessId# </isNotEmpty>
<isNotEmpty prepend=" AND " property="state">
i.STATE = #state# </isNotEmpty>
<isNotEmpty prepend=" AND " property="noticeShowType">
n.NOTICE_SHOW_TYPE = #noticeShowType# </isNotEmpty>
<isEqual property="saleBack" compareValue="10" prepend=" AND ">
n.NOTICE_TYPE!='25'</isEqual>
<isEqual property="remittanceBank" compareValue="10" prepend=" AND ">
n.NOTICE_TYPE!='63'</isEqual>
<isEqual property="remittanceOnline" compareValue="10" prepend=" AND ">
n.NOTICE_TYPE!='64'</isEqual>
)row_ where rownum <=1 ) where rownum_>=0
</select>