hibernate 1
hibernate 3.5.3
在使用hibernate 继承关联映射时，一个继承树对应一个表
错误提示：
org.hibernate.MappingException: Could not format discriminator value to SQL string
Caused by: java.lang.NumberFormatException: For input string: "com.test.domain.Users"
org.hibernate.InvalidMappingException: Could not parse mapping document from resource com/test/domain/Regions.hbm.xml
Caused by: org.hibernate.DuplicateMappingException: Duplicate class/entity mapping com.test.domain.Regions
解决办法：在class元素中加入discriminator-value="not null" 属性
参考：http://dev.csdn.net/htmls/82/82734.html
