Container-Managed Persistence - IV
Bean provider gives the field of the bean class containing the primary key with "primkey-field" tag in the deployment descriptor. Bean provider does not have to define a primary key in that case the deployment tool decides on this. But the bean class implementation should not be rely on any specific type of primary key accept that it will be java.lang.Object type.
Bean provider must specify this.
Bean must implement javax.ejb.EntityBean interface.