On 23/02/2026 14:18, Michael Stover wrote:
I've been using Scoped Values heavily for some time for a variety of
things and just thought I'd share a couple thoughts . I'm currently
using JDK 25.
First, really simply, the ScopedValue.get() method throws a runtime
exception if the value is not bound. Ok, kind of like Optional. But,
it seems ScopedValue.orElse(null) also throws a runtime exception,
which makes it awkward to safely get the currently scoped value or
null. Instead we have to do:
if(scopedValue.isBound()) return scopedValue.get();
else return null;
Or use a static NullObject pattern. If we give orElse() a new Object,
we're creating that new object every time regardless of whether it's
needed. So, calling isBound() all the time seems overly verbose and
tedious, and it appears to be a bit of a performance hit from my
testing as well, as it's an expensive operation, and I guess we're now
doing it twice.
So I think that could be improved so one can get a null out, or at
least give us an idiom that isn't a performance drag.
Using a sentinel value, like your NullObject, should be okay.
orElse(T) is specified to reject null to allow it be compatibly changed
to T! in the future.
-Alan
