UML class diagrams are useful when modeling business data. By accurately modeling attributes and associations of class entities, we can easily map these class diagram specifications to entity beans with CMP. Class attributes map to abstract access methods for persistent fields, and association roles map to abstract access methods for relationship fields. Navigability determines whether relationship access methods appear in both related entity beans or just one. Furthermore, multiplicity notation determines the correct type for relationship fields, life cycle issues, and cascading delete characteristics.