Class Diagram Part II

Hello

I am using JPA in my assignment but I have doubts, I have watched different points of view related to the level of detail in the class diagram, but I think to show a complete solution, I need to add in the diagram, the EntityManager and the Query interfaces, but I do not know how to put them in the diagram, Is correct to add them like interfaces showing the methods I am using or I should treat them like implementation classes ?

Thanks in advance.

Even I am using JPA in my assignment but I am not mentioning about EntityManager in class diagram, my is more or less similar to Cade's sample assignment. About the EntityManager its described in sequence diagram rather than class diagram.

If you want to use better split the class diagram into Web tier , business and EIS tier.

In my class diagram i'am not showing that much detail, showing the controller, session beans,jsp's , pojo's and their relationships.

Thank's kumar naresh and Sreenivas P Kumar, but I think, that is the point, I read that all the elements you are showing in the sequence diagram must be present in the class diagram.
A lot of people think the Cade's sample has many errors (http://www.coderanch.com/how-to/java/CadeSheilSceaFaq).

¿Could I lose marks if I add these classes?

Greetings