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Gotchas

The following is a quick checklist of “gotchas” to help you with your implementation:

• If the primary key is composite, a custom primary key class must be defined. The fields of this class must be public and must correspond in name and type to cmp-fields of the bean class.

• cmp-field and cmr-field fields must begin with a lowercase letter, (so that it can be capitalized in the corresponding getter and setter method names).

• If a collection is returned from a cmr-field's getter method, it must not be modified other than through Iterator.remove() (see EJB specification, section 10.3.6.1).

• Collections returned by getter methods cannot be used outside of the transaction context in which they were materialized.

• If a bean has no relationships, the ...