spring中map的定义, 包括value为class的定义

     <bean id="fieldMap" value-ref="obj"></entry>                    <entry key="reserve_price" value-ref="double"></entry>                    <entry key="auction_status" value-ref="obj"></entry>                    <entry key="quantity" value-ref="obj"></entry>                    <entry key="options" value-ref="obj"></entry>                    <entry key="spu_id" value-ref="obj"></entry>                    <entry key="sold_quantity" value-ref="obj"></entry>                    <entry key="features" value-ref="obj"></entry>                    <entry key="category" value-ref="obj"></entry>                    <entry key="user_id" value-ref="obj"></entry>                    <entry key="auction_id" value-ref="obj"></entry>                    <entry key="gmt_modified" value-ref="date"></entry>                    <entry key="pict_url" value-ref="obj"></entry>                    <entry key="sync_version" value-ref="obj"></entry>               </map>          </property>     </bean>     <bean id="date" factory-method="forName">          <constructor-arg value="java.util.Date"/>     </bean>     <bean id="double" factory-method="forName">          <constructor-arg value="java.lang.Double"/>     </bean>     <bean id="obj" factory-method="forName">          <constructor-arg value="java.lang.Object"/>     </bean>