Details
-
Bug
-
Status: Closed
-
Major
-
Resolution: Fixed
-
2.5.8, 3.0.0
-
None
-
None
Description
Follow up to GROOVY-8519. Suggestions for new extension methods for Java 8's Optional and Stream:
def opt = Optional.ofNullable(...) opt.filter(Type) // DGM that is shorthand for opt.filter(it -> it instanceof Type).map(it -> (Type) it) // result is Optional<Type> // methods available on Stream, but missing for Optional: opt.mapToInt(...) // DGM that accepts ToIntFunction and returns OptionalInt opt.mapToLong(...) // DGM that accepts ToLongFunction and returns OptionalLong opt.mapToDouble(...) // DGM that accepts ToDoubleFunction and returns OptionalDouble opt.stream() // DGM that is shorthand for opt.map(Stream::of).orElseGet(Stream::empty) // useful for Stream.concat() or generally interfacing with stream-based APIs // add get() to OptionalInt, OptionalLong and OptionalDouble as shorthand for getAsInt(), etc. OptionalInt optInt = ... optInt.filter(i -> ...) // accepts IntPredicate and returns OptionalInt. Not sure why this is missing from OptionalInt, but this allows testing the value against some criteria. // similarly for OptionalLong and OptionalDouble def one = Stream.of(...) def two = Stream.of(...) def str = one + two // plus() overload for stream as shorthand for Stream.concat() str = str + obj // plus() overload for Stream.concat(str, obj.stream()) str << obj // leftShift() overload; may make sense, may not def str2 = Stream.ofNullable(obj) // DGSM to return Stream.empty() for null and Stream.of(obj) for non-null -- exists in Java 9+ // or maybe a general stream(Object) so you could do this instead: def str3 = obj.stream() // Stream.empty() for null and Stream.of(obj) for non-null
Attachments
Issue Links
- links to
