MyBatis/Ibatis :-关于Ibatis/Mybatis中查询的帮助

Question

我写了一个查询：

 <select id="fetchEndPointArn" parameterType="map"   resultType="com.rohit.service.model.UserActive">
     select userid,endpointarns from t_user_actives where sid=#{sid}  
     and (userid in
     <foreach item="userid" index="index" collection="userid" open="(" separator="," close=")">
        #{userid}
     </foreach>
          )
 </select>

我的DaoImpl:-

@Override
public List<UserActive> fetchEndPointArn(Map<String,String> map) {
    List<UserActive> userActive=sqlSession.selectList("fetchEndPointArn",map);
    return userActive;
}

我传递的map包含:-

sid=10,userid=t10,t12

我收到了一个异常提示:-

Error evaluating expression 'userid'.  Return value (t10,t12) was not iterable

Answer 1

将参数类型更改为java.util.Map。将您的集合定义为collection="list" instead of collection="userid"。最后，让userid成为一个数组列表，如下所示

List userid = new ArrayList();
userid.add("t10");
userid.add("t12");
Map paramMap = new HashMap();
paramMap.put("sid",10);
paramMap.put("userid",userid);

然后在您的xml中

 <select id="fetchEndPointArn" parameterType="java.util.Map"   resultType="com.rohit.service.model.UserActive">
     select userid,endpointarns from t_user_actives where sid=#{sid}  
     and userid in
     <foreach item="userid" collection="list" index="index" open="(" separator="," close=")">
        #{userid}
     </foreach>
 </select>