public static RelationalDescriptor descriptor() {
    RelationalDescriptor descriptor = new RelationalDescriptor();

    /* First define the class, table and descriptor properties. */
    descriptor.setJavaClass(Customer.class);
    descriptor.setTableName("EVENTCUSTOMER");
    descriptor.setPrimaryKeyFieldName("ID");
    descriptor.setSequenceNumberName("SEQ");
    descriptor.setSequenceNumberFieldName("ID");

    /* Next define the attribute mappings. */
    OneToOneMapping addressMapping = new OneToOneMapping();
    addressMapping.setAttributeName("address");
    addressMapping.setReferenceClass(Address.class);
    addressMapping.dontUseIndirection();
    addressMapping.privateOwnedRelationship();
    addressMapping.addForeignKeyFieldName("EVENTCUSTOMER.ADDRESS_ID", "EADDRESS.ID");
    descriptor.addMapping(addressMapping);

    OneToOneMapping phoneMapping = new OneToOneMapping();
    phoneMapping.setAttributeName("phoneNumber");
    phoneMapping.setReferenceClass(Phone.class);
    phoneMapping.dontUseIndirection();
    phoneMapping.privateOwnedRelationship();
    phoneMapping.addForeignKeyFieldName("EVENTCUSTOMER.PHONE_ID", "EPHONE.ID");
    descriptor.addMapping(phoneMapping);

    OneToOneMapping emailMapping = new OneToOneMapping();
    emailMapping.setAttributeName("email");
    emailMapping.setReferenceClass(EmailAccount.class);
    emailMapping.dontUseIndirection();
    emailMapping.privateOwnedRelationship();
    emailMapping.addForeignKeyFieldName("EVENTCUSTOMER.EMAIL_ID", "EMAILACC.ID");
    descriptor.addMapping(emailMapping);

    DirectCollectionMapping associationsMapping = new DirectCollectionMapping();
    associationsMapping.setAttributeName("associations");
    associationsMapping.dontUseIndirection();
    associationsMapping.setReferenceTableName("EASSOCIATIONS");
    associationsMapping.setDirectFieldName("EASSOCIATIONS.DESCRIP");
    associationsMapping.addReferenceKeyFieldName("EASSOCIATIONS.CUSTOMER_ID", "EVENTCUSTOMER.ID");
    descriptor.addMapping(associationsMapping);

    OneToManyMapping ordersMapping = new OneToManyMapping();
    ordersMapping.setAttributeName("orders");
    ordersMapping.setReferenceClass(Order.class);
    ordersMapping.useBasicIndirection();
    ordersMapping.addTargetForeignKeyFieldName("EVENTORDER.CUSTOMER_ID", "EVENTCUSTOMER.ID");
    descriptor.addMapping(ordersMapping);

    AggregateObjectMapping creditMapping = new AggregateObjectMapping();
    creditMapping.setAttributeName("creditCard");
    creditMapping.setReferenceClass(org.eclipse.persistence.testing.models.events.CreditCard.class);
    creditMapping.setIsNullAllowed(true);
    descriptor.addMapping(creditMapping);

    descriptor.addDirectMapping("id", "ID");
    descriptor.addDirectMapping("name", "NAME");

    return descriptor;
  }