The purpose of these diagrams is to help grasp what's going on when issuing a db.commit() on objects with relationships. The following examples all use the same objects, Book and Author, but with different relationships between them.

(Note: the diagrams, along with complete test code, can also be found at http://jira.codehaus.org/browse/CASTOR-2854)

No relationship (Author)

changing a field of Author

One-to-one relationship (Author <-- Book)

changing a field of Author

setting a new Author

One-to-many relationship (Author --> Book)

Sequence diagrams for db.commit()

No relationship (Author)

changing a field of Author

One-to-one relationship (Author <-- Book)

changing a field of Author

setting a new Author

One-to-many relationship (Author --> Book)

add a new Book