Please, let's not derail this thread. :-)
I think would be a good thing to think about, so I've filed a JIRA issue to
track it:
https://bugs.openjdk.java.net/browse/JDK-8193279
s'marks
On 12/8/17 1:45 AM, Remi Forax wrote:
Let's gently derail this thread, the is another pain point with the current
optional API,
it seems that are no simple way to transform an Optional<Integer> to an
OptionalInt and vice-versa.
It's painful because we start to see interface that returns by example OptionalInt
while the implementation you want to connect with return an Optional<Integer>.
The only workaround seems to be to use a Stream/IntStream:
Optional -> OptionalInt
optional.stream().mapToInt(x -> x).findFirst()
OptionalInt -> Optional
optionalInt.stream().boxed().findFirst();
I think, Optional should have the method mapTo*/flatMapTo* and
Optional[Primitive] the method boxed().
regards,
Rémi
----- Mail original -----
De: "Stuart Marks" <stuart.ma...@oracle.com>
À: "core-libs-dev" <core-libs-dev@openjdk.java.net>
Envoyé: Vendredi 8 Décembre 2017 01:33:41
Objet: RFR(s): 8140281 add no-arg Optional.orElseThrow() as preferred
alternative to get()
Hi all,
Please review this changeset that introduces a new no-arg method orElseThrow()
to Optional, as a preferred alternative to the get() method.
Corresponding methods are also added to OptionalDouble, Int, and Long.
The orElseThrow() method is functionally identical to get(). It has some
affinity with the existing orElseThrow(exceptionSupplier) method, being
equivalent to orElseThrow(NoSuchElementException::new).
The get() method is functionally unchanged. It is NOT being deprecated, although
some wording in the doc has been added to point to orElseThrow() as the
"preferred alternative." This is part of a (slow) migration away from
Optional.get(), which has an obvious, attractive name that is often misused.
These issues have been discussed on this list previously:
http://mail.openjdk.java.net/pipermail/core-libs-dev/2016-April/040484.html
Please note that much of that discussion was about the then-proposed deprecation
of Optional.get(), which is NOT part of this proposal. There are no plans to
deprecate Optional.get() at this time. This proposal ONLY introduces a new
method orElseThrow() that is identical in function to get().
Bug report:
https://bugs.openjdk.java.net/browse/JDK-8140281
Webrev:
http://cr.openjdk.java.net/~smarks/reviews/8140281/webrev.1/
Thanks,
s'marks
