ibatis遍历数组:ParameterObject or property was not a Collection, Array or Iterator.

这个问题在使用ibatis的<iterate></iterate>时出现的,很简单,但是蛋疼了很久,记下来

首先从错误提示看,明显意思是你给出ibatis的参数不对路,人家不认识,我也是被这个提示误导了

1.先来个小学的

//传入的参数只有数组/集合/迭代器的时候
public List findall(SqlMapClient sqlMap, String[] ids) throws SQLException{
        return sqlMap.queryForList("findall",ids)
    }

<!--传入值唯一数组,所以甚至这么干就行-->
<statement id="findall" resultClass="..User">        
        select * from user_table where id in
        <iterate open="(" close=")" conjunction=",">
            #[]#
        </iterate>
    </statement>

<!--r如果是list需要加个参数类型,然后指定下-->

<statement id="findall" resultClass="..User" parameterClass="java.util.List">        
        select * from user_table where id in
        <iterate open="(" close=")" conjunction=",">
            #ids[]#
        </iterate>
    </statement>

 2.来个中学的(倒在这里了)

//传入对象,那么User中有个属性叫爱好  hobbies[]  同时form传递来的字段叫hobby
public List findAll(SqlMapClient sqlMap,User user){
    return   sqlMap.queryForList("findall",user);  

}

//
<statement id="findall" parameterClass=="...User" resultClass="...User">
select * from table_user where 1=1
  <isNotEmpty property="org_ids" prepend="and"> 
     hobby in
         <iterate property="hobbies" open="(" close=")" conjunction=","> 
          #hobbies[]#
        </iterate>
  </isNotEmpty>
</statement>

3.还没用过大学的map遍历 对象遍历 就不说了

 

慢慢看这个

http://hongzhguan.iteye.com/blog/1222353