Claude
6b5a918278
gatherers/: windowFixed, windowSliding, fold, scan, mapConcurrent, a custom Gatherer (dedupeConsecutive, takeUntil), and a Collector-vs-Gatherer comparison. Verified: windowSliding emits one short window on a too-short stream rather than shrinking to empty like windowFixed; mapConcurrent waits for in-flight siblings to finish (~901ms) rather than cancelling them when one mapper throws. scoped-values/: ScopedValue API and rebinding, why plain threads (virtual or platform) do not inherit a binding while a StructuredTaskScope subtask does, and the memory cost vs InheritableThreadLocal measured two ways -- a noisy heap-delta first pass, then a precise jcmd GC.class_histogram object census (5 shared Carrier objects vs ~700,000 copied ThreadLocalMap/Entry objects for 100,000 threads). Companion code for the ankurm.com posts "Java Stream Gatherers (JEP 485)" and "Scoped Values vs ThreadLocal in Java 25: Migration Guide with Virtual Threads". Co-Authored-By: Claude Sonnet 5 <[email protected]> Claude-Session: https://claude.ai/code/session_01FtpJvZfg4nvLvtzgJTDWpB
8 lines
506 B
Plaintext
8 lines
506 B
Plaintext
$ java CustomGatherer (JDK 25)
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dedupeConsecutive of a,a,b,b,b,a,c,c = [a, b, a, c]
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CHECK ok : consecutive runs collapse to [a, b, a, c]; the second 'a' survives because it isn't adjacent to the first
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takeUntil(n == 3) result = [1, 2, 3], upstream elements actually pulled = [1, 2, 3]
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CHECK ok : takeUntil includes the element that satisfies the stop condition: [1, 2, 3]
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CHECK ok : the upstream peek() only saw 1, 2, 3 -- elements 4, 5, 6 were never pulled, this genuinely short-circuits
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exit=0
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