HI,
first sorry for missing the class wide definition.
Am 02.03.2017 um 12:45 schrieb Vitaly Davidovich:
On Thu, Mar 2, 2017 at 6:38 AM Ulf Zibis <ulf.zi...@cosoco.de
<mailto:ulf.zi...@cosoco.de>> wrote:
In any case, what's the reasonable of checking an argument, which is not
used in that case?
My understanding is contracts like the above (let's assume it still called out the NPE in 8) are
checked even if the argument isn't used in some cases. The other case where I believe this is
done is when passing a Supplier to some method that uses it to obtain a default value - even if
it's not needed, it's checked for null because most (all?) such methods stipulate that it cannot
be null.
On the other hand, the null check is a waste of performance and footprint (implicits performance
cost too).
I can't imagine, if any programmer would rely on such contract, instead of doing the check
explicitly if of significance.
I think, the original reasonable of the contract is to rule out any other exception type or
undefined behaviour in case of relevance of the argument. So I would vote for stating the contract
more precisely in that way.
Also, if I remember correct, if a variable, here replStr, is only referenced later, the compiler can
move the execution of here replacement.toString() to a later position, so it is not clear to me, if
the original implementation ever fulfilled the contract.
-Ulf
