Error in MZ notes - EntityManager.find

[Treimin Clark]

This is about the EntityManager.find method.

According to the MZ notes:

MZ Notes wrote:If the instance is already present in the current persistence context, the cached version will be returned. Otherwise, a new instance will be constructed and loaded with state from the datastore.

But the "Pro EJB 3" book says

Pro EJB 3 wrote:In the event that the object was not found, then the find() call simply returns null. We would need to ensure that a null check is performed before the next time the emp variable is used.

I think that this is an error with Maikali Zaikin's notes. Am I correct?

[Raf Szczypiorski]

MZ notes say about a case when the entity was not in the first-level cache (was not managed).
The book says about a case when the entity with the specified key was not found in the cache, and also could not be found in the database.

[Treimin Clark]

Raf Szczypiorski wrote:MZ notes say about a case when the entity was not in the first-level cache (was not managed).
The book says about a case when the entity with the specified key was not found in the cache, and also could not be found in the database.

Oh! Thanks. I understood.