This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
In HFEJB 420, in the BulletPoint about Cascade-delete,it says, Cascade-delete works only if the bean has a multiplicity of One. In Page 395, DirectorBean has Multiplicity as One and MovieBean has Multiplicity as Many. Here Cascade-delete comes in MovieBean? Am I missing something here?
You can optionally specify a role as Cascade-delete in the DD if and only if the OTHER PARTY in the relationship has a multiplicity of One.
This means that Many-to-Many relationships cannot have Cascade-delete in either of the 2 ends (roles).
I hope this does not confuse you but it helps me : I always think of the role as having Cascade-delete as the "weaker" role. The Movie role is "weaker", that's why it is allowed to have the optional Cascade-delete attribute. "Weaker" in the sense that when a Director is deleted, all the movie bean related to that director will be deleted. The "power" is at the Director's end (role).
Joined: Dec 13, 2002
Thank you timothy, I got it now, so its the other party in the relationship should have multiplicity one.