JiafanZhou wrote:
Recently I have been preparing for the SCBCD exam, and I found the EJB3.0 specification is very very strict about using the static fields/members for the session and message-driven beans.

It also proves the concept that using static is not thread-safe, I believe this is the reason for the EJB3.0 specification.

Quoted from the EJB 3.0 specification.

A field or method of a bean class may be annotated to request that an entry from the bean's environment be injected. Any of the types of resources or other environment entries described may be injected. Injection may also be requested using entries in the deployment descriptor corresponding to each of these resource types.

The field or method MAY have any access qualifier, but <u>MUST NOT</u> be static.

In other words, EJB experts have the same concerns like me that using static fields could seriously compromise the thread safety.

Regards,
Jiafan