it can be :
1. transaction readonly bean -- don't need roll back.
2. transaction bean -- which transaction may need roll back.
3. no transaction bean
..
..
biz method can be put in a POJO, what you need to do is just call this POJO in the generic session bean.
1 共享ejb容器底层服务,包括缓冲池,事务管理,事实上无状态ejb明显强于
普通bean
2 降低组件的耦合度,将业务逻辑通过一层映射机制与web层分里,
可以使ejb的客户端配置跟灵活