我想实现对数据表的批量查询，但出现如下错误：

2006-04-04 19:18:21,878 DEBUG [com.jdon.container.visitor.HttpSessionProxyVisitor] get the optimized instance for the key com.jdon.framework.test.service.MessageServicePOJOImpproxyInstanceFactoryVisitable

2006-04-04 19:18:21,878 ERROR [com.jdon.framework.test.web.MessageListAction] java.lang.ClassCastException: java.lang.Integer

2006-04-04 19:18:21,888 WARN [com.jdon.strutsutil.ModelListAction] the model Id=(1) maybe be deleted!

2006-04-04 19:18:21,888 DEBUG [com.jdon.strutsutil.ModelListAction] listForm 's property: getList size is 0

应该是出现类型冲突,表的主键是int型,字符型的可似实现.谢谢