J2EE questions

03-12-18 i_love_this_game
    

Hi, all,

first time to this form ,

following are questions from exam. can anybody give me a answer?

1. why are activation and passivation so important for EJB technology? What enterprise computing problems are addressed by these mechanism? how does the EJB container implement the process of activation and passivation in SessionBean and Entity Bean?

2. Describe the mechanism adopted by the EJB container to manage the persistence of an entity bean's state. How does this mechanism differ between entity beans using CMP & entity beans using BMP?

thanks in advance.

    

banq
2003-12-18 16:05

activation 和 passivation 其实对于EJB使用并不重要,一般使用无状态Session Bean无需关心 activation and passivation 。

activation 和 passivation是EJB容器实现的内部过程,对于一般EJB使用者无需关心,如果你想做J2EE 容器软件开发,如JBoss等,可以钻研一下。

第二个问题是,现在如果需要事务就用CMP,读取使用DAO+JDBC,更新的方案是使用JDO,BMP已经被逐步抛弃,只能在旧代码中看到。

这个试题不回答也罢。

i_love_this_game
2003-12-18 16:59

thanks.

banq

These two are sample questions from exam. they contribute 12 marks for total score. The real exam question may not be same but could be similar. I must answer them

thanks again for ur answer

daquan198163
2004-02-05 09:33

你在哪读书呢,大几了:)?

henry.t
2004-02-05 17:06

从 i_love_this_game 我猜应该是在地球那一边吧,呵呵,你看英文多溜。不过我到现在对有些概念还不是很清楚,比如,DAO到底是什么东西?是一个概念还是一个解决方案

2Go 1 2 下一页