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APIs should use a combination of these approaches both to help clients distinguish correct results from incorrect ones and to encourage careful handling of any incorrect results. In some cases, an error value instead of an exception should be returned, and vice versa; and in other cases an exception should be thrown. A method should not return a value that can hold both valid return data and an error code; see ERR52-JG. Avoid in-band error indicators for more details.
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