RFR: 8253176: Signature.getParameters should specify that it can throw UnsupportedOperationException [v2]

[Valerie Peng]

On Wed, 27 Apr 2022 23:30:22 GMT, Valerie Peng <valeriep at openjdk.org> wrote:

>> Can you clarify what is the A and B that you are referring to? The way I read it, it has more than 2 conditions... So, best to clarify the conditions first. 
>> I see your point with the wording suggestion at the end. Was a bit lost when trying to go through the various if-else logic and figure out what you mean...
>
> With Signature class, there is a caveat for EdDSA, the supplied parameters are set but null is being returned when getParameters() is called. This is currently covered by the condition `if the underlying signature implementation supports returning the parameters as {@code AlgorithmParameters}` as the underlying signature does not support AlgorithmParameters for the supplied EdDSAParameterSpec object due to lack of ASN.1 definition.

Besides this Signature-specific condition, there is the common condition where provider cannot (or do not) generate default parameter values. {@code null} is used as the catch-all result, but as you said, describe various conditions tersely and correctly is key.

-------------

PR: https://git.openjdk.java.net/jdk/pull/8396