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Defining which updatable collections have deletable elements
org.kuali.rice.kns.bo.PersistableBusinessObject.buildListOfDeletionAwareLists() should be implemented for all business objects that require deletion of removed elements.
In a nutshell, this method returns a List of Collection of a BO. It returns a list of references to the actual collections storing data. Given a BO from the form to persist, it retrieves the corresponding BO from the database (based on primary key). Compares the collections returned by buildListOfDeletionAwareLists(), and deletes any elements contained within the DB-based BO and not in the form-based BO.
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