This is a very nice patch, complete with spec and tests, and evidence of OCA. But, before we talk about patches and code, let's step back and talk about stewardship. With API proposals, we like to start with problems, rather than solutions: what problems we are concerned with, and are these are problems that need to be solved in the JDK? Assuming we like the answers to the former, we can then move on to whether the proposed solution is the right one, and then to details like spec and code review. We are currently trying to avoid adding anything to OptionalInt/Long/Double, because our current plan is to replace these with a specialized Optional<int> once Valhalla delivers. Any methods that differ from the base type (Optional) creates potential roadblocks to such a migration, so we'd prefer to leaves these classes be. To the main question, though, whether Optional should have specialized map and flatMap methods ... I'm skeptical. The goal was never to create parity between Optional and Stream, and my gut reaction is that the return on additional API surface area here is negative. But, we can surely have a discussion on this. On 2/16/2019 7:52 AM, Rob Spoor wrote:
I noticed that, while Stream and its primitive equivalents have multiple map and flapMap methods, Optional and its primitive equivalents were missing those. Since these can still be very useful, I wrote a patch to add the following methods:
* Optional: mapToInt, mapToLong, mapToDouble, flatMapToInt, flatMapToLong, flatMapToDouble * OptionalInt: map, mapToObj, mapToLong, mapToDouble, flatMap * OptionalLong: map, mapToObj, mapToInt, mapToDouble, flatMap * OptionalDouble: map, mapToObj, mapToInt, mapToLong, flatMap
I did not add any more flatMap methods to OptionalInt, OptionalLong and OptionalDouble because these also don't exist on IntStream, LongStream and DoubleStream.
In addition, I also added the missing or method to OptionalInt, OptionalLong and OptionalDouble based on that of Optional.
My OCA has been processed on 2019-01-22.
Rob