Duplicate class/entity mapping 问题解决方法
开发环境：myeclipse8+spring2.5+hibernate3+mysql5
首先在mysql中建立表t，然后使用myeclipse中 Db视图，选择该表t，使用反转功能生成 hibernate.cfg.xml +pojo+tDAO+HibernateSessionFactory+t.hbm.xml
建立main类，访问数据库，报错：
Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'TDAO' defined in file [D:\Workspaces\MyEclipse 8.6\Demo\src\applicationContext.xml]: Cannot resolve reference to bean 'sessionFactory' while setting bean property 'sessionFactory';
...
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sessionFactory' defined in file [D:\Workspaces\MyEclipse 8.6\Demo\src\applicationContext.xml]: Invocation of init method failed; nested exception is org.hibernate.DuplicateMappingException: Duplicate class/entity mapping T
...
Caused by: org.hibernate.DuplicateMappingException: Duplicate class/entity mapping T
...
解决方法：
hibernate.cfg.xml 中session-factory ,配置了
<mapping resource="T.hbm.xml" />
此项和applicationContext.xml 中 sessionFactory 的
<property name="mappingResources">
<list>
<value>T.hbm.xml</value>
</list>
</property>
冲突， 把hibernate.cfg.xml 中 的<mapping resource=""/> 注销即可