ibatis resultClass==hashmap resultClass提供几种类型

今天遇到一个问题：

Caused by: com.ibatis.common.jdbc.exception.NestedSQLException:   
--- The error occurred in com/inspur/paas/attachment/dao/attachment.xml.  
--- The error occurred while applying a result map.  
--- Check the Attachment.getAppAttachmentByAppId-AutoResultMap.  
--- Check the result mapping for the 'id' property.  
--- Cause: java.lang.RuntimeException: JavaBeansDataExchange could not instantiate result class.  Cause: java.lang.InstantiationException: java.util.Map

 

 

 

<select id="getAppAttachmentByAppId" parameterClass="string" resultClass="hashmap">
		select app_id,email,attachment_id,id from gov_item_express_info  where app_id = #app_id#
	</select>

 

 

 resultClass="hashmap"  ---使用map报错

 

 

ibatis结果集resultClass的几种类型

http://www.jcodecraeer.com/a/chengxusheji/java/2013/0102/771.html

摘要 ibatis在编写sqlmap的查询时，可以配置多种输出格式，比如：实体类，hashmap，xml格式。 sqlmap中的hashmap和xml都是内置别名。 1.实体类： resultMap id="UserResult" class="User"result property="id" column="T_ID"/result property="name" column="T_NA

ibatis在编写sqlmap的查询时，可以配置多种输出格式，比如：实体类，hashmap，xml格式。
sqlmap中的hashmap和xml都是内置别名。

1.实体类：

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<resultMap id="UserResult" class="User">    <result property="id" column="T_ID"/>    <result property="name" column="T_NAME"/>    <result property="sex" column="T_SEX"/>    <result property="address" column="T_ADDRESS"/>    </resultMap>           <select id="selectAllUser" resultMap="UserResult"> select * from t_user </select>       List list = userdao.selectAllUser(); for(int i=0;i<list.size();i++) { System.out.println(list.get(i)); }

注：当作一个对象使用。

2.hashmap:

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<select id="selectAllUser" resultClass="hashmap"> select * from t_user </select>       List list = userdao.selectAllUser();    for(int i=0;i<list.size();i++) {    Map map = (Map)list.get(i);    System.out.print(map.get("id")+" ");    System.out.print(map.get("name")+" ");    System.out.print(map.get("sex")+" ");    System.out.print(map.get("address"));    System.out.println();    }

注：当作一个键值对的MAP使用。

3.XML：

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<select id="selectXML" resultClass="xml" xmlResultName="log"> select * from t_user </select> List list = userdao.selectAllUser();    for(int i=0;i<list.size();i++) {    System.out.println(list.get(i));    }

 

XML结果：

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<?xml version="1.0" encoding="UTF-8"?><log><id>1</id><name>hua</name><***>1</***><address>1</address></log> <?xml version="1.0" encoding="UTF-8"?><log><id>2</id><name> zhupan </name><***>2</***><address>1</address></log> <?xml version="1.0" encoding="UTF-8"?><log><id>4</id><name> 4 </name><***>4</***><address>1</address></log> <?xml version="1.0" encoding="UTF-8"?><log><id>5</id><name> 5 </name><***>5</***><address>2</address></log>