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https://issues.apache.org/jira/browse/JENA-1427?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16273015#comment-16273015
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ASF GitHub Bot commented on JENA-1427:
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Github user ajs6f commented on the issue:
https://github.com/apache/jena/pull/323
I'm saying we don't do `orElseThrow` or any other `orElseX`, we leave that
to `nextOptional().orElseThrow()`, etc. Then at iterator end, `nextOptional()`
returns `empty` forever. If there are `null`s, it returns `empty`. If you want
to know whether that is because there are many `null`s or because the iterator
is done, you call `hasNext()`.
Another way to put it: we shouldn't try to eliminate needing `hasNext()`
with this-- if we want to do that, we should do something like
`Spliterator::tryAdvance`, which is a whole different story. You can se how
that would work a little with `Iterator::forEachRemaining`. You don't need
`hasNext()` with that.
> Add nextOrElse() method in ExtendedIterator
> -------------------------------------------
>
> Key: JENA-1427
> URL: https://issues.apache.org/jira/browse/JENA-1427
> Project: Apache Jena
> Issue Type: Improvement
> Components: Core
> Affects Versions: Jena 3.5.0
> Reporter: Adam Jacobs
> Priority: Trivial
> Labels: easytask
>
> Allow a functional approach for returning a default value or throwing a
> custom exception from a Jena iterator.
> The following method may be added to the ExtendedIterator interface.
> {noformat}
> /**
> Answer the next object, if it exists, otherwise invoke the
> _supplier_.
> */
> public default T nextOrElse( Supplier<T> supplier ) {
> return hasNext() ? next() : supplier.get();
> }
> {noformat}
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