On 6/21/2018 12:33 AM, Tagir Valeev wrote:
Please review and sponsor:
https://bugs.openjdk.java.net/browse/JDK-8205461
http://cr.openjdk.java.net/~tvaleev/webrev/8205461/r1/
See also previous discussion thread at [1]. It seems that we did not reach
the final conclusion about the collector name, so in this review it's still
named as "pairing" (proposed by me). Other name proposals:
None of the names so far are great. The essential challenge in naming
here is that this Collector does two (or maybe three) things: duplicate
the stream into two identical streams ("tee"), sends each element to the
two collectors ("collecting"), and then combines the results
("finishing"). So all the one-word names (pairing, teeing, unzipping,
biMapping) only emphasize one half of the operation, and names that
capture the full workflow accurately (teeingAndCollectingAndThen) are
unwieldy.
Of the three phases, teeing is the most important and least obvious, so
I think something that includes that in the name is going to be
helpful. Perhaps "teeingAndThen" is more evocative and not totally
unwieldy.
Names along the lines of "merging" may incorrectly give the idea that
the merge is happening elementwise, rather than duplicating the streams,
collecting, and merging the results.
By the way looking into CollectorsTest.java I found some minor things to
cleanup:
1. `.map(mapper::apply)` and `.flatMap(mapper::apply)` can be replaced with
simple `.map(mapper)` and `.flatMap(mapper)` respectively
Does IntelliJ have an inspection for eliminating such locutions?
2. In many methods redundant `throws ReflectiveOperationException` is
declared while exception is never thrown
For test code where a significant fraction of test cases are going to
throw something, we often do this, since its easier to just uniformly
tag such methods rather than thinking about which test methods actually
throw the exception and which don't. So I think this is harmless
(though cleaning it up is harmless too.)
You may want to optimize the EnumSet mechanics for the case where
neither collector has interesting characteristics.
