isNotNull与isNotEmpty的区别

<isNotNull>

检查属性是否不为null

<isNotEmpty>

检查Collection.size()的值，属性的String或String.valueOf()值,是否不为null或不为空（“”或size() > 0） 

 

----------------------使用----------------------

<!-- 分页查询返回列表 -->
<select id="getUserPrivacyPage" parameterClass="map" resultClass="hashmap">
select uid,`key`,`value` from ts_user_privacy
    <dynamic prepend="WHERE">
        <isNotEmpty prepend="AND" property="uid">
        uid=#uid#
        </isNotEmpty>
        <isNotEmpty prepend="AND" property="key">
        key=#key#
        </isNotEmpty>
        <isNotEmpty prepend="AND" property="value">
        value=#value#
        </isNotEmpty>
    </dynamic>
    <isNotEmpty prepend="order by " property="_order">
    $_order$
    </isNotEmpty>
    <isNotEmpty prepend="limit " property="_limit">
     #_limit._pstart#,#_limit._psize#
    </isNotEmpty>
</select>

  <!-- 修改记录 -->

<update id="updateUserPrivacy"  parameterClass="map">
update ts_user_privacy
    <dynamic  prepend="set">
        <isNotNull prepend=","  property="value"> `value`=#value# </isNotNull>
    </dynamic>
    where uid=#uid# AND `key`=#key#
</update>

 

http://huangqiqing123.iteye.com/blog/1668963