rootvector2 opened a new pull request, #425:
URL: https://github.com/apache/commons-beanutils/pull/425

   Follow-up to #419, where 
`WrapDynaClassTest.testConcurrentCreateDynaClassReturnsSameInstance` failed on 
1.X CI 
([run](https://github.com/apache/commons-beanutils/actions/runs/29845745287/job/88685774320)).
   
   The failure is the test asserting more than the cache guarantees, not the 
synchronization from #419. The per-classloader cache is weak-keyed 
(`WeakFastHashMap` delegates to `WeakHashMap`) and the `CacheKey` is referenced 
by nothing but the map, so any GC evicts the entry and the next 
`createDynaClass` call legitimately builds a new instance. No concurrency is 
needed to see it: on unmodified 1.X, `createDynaClass`, `System.gc()`, 
`createDynaClass` returns a distinct second instance. When a GC lands inside 
one of the test's rounds, a late thread misses the cache and the round observes 
two instances — exactly the CI failure (`expected: <1> but was: <2>`). Master 
is unaffected because the beanutils2 cache (`ConcurrentReferenceHashMap`) holds 
soft references, which survive ordinary GCs.
   
   The fix allocates a `WeakReference` canary at the start of each round and 
only asserts the single-instance property when the canary shows no GC ran 
during the round; rounds a GC invalidated are skipped. 
`testCreateDynaClassIsCached` gets the same guard since it has the same 
sensitivity in a smaller window.
   
   Verified locally:
   
   - the guarded test still fails on the pre-#419 unsynchronized code, so the 
regression coverage is intact
   - a temporary `System.gc()` hammer thread makes the unguarded test fail 
immediately with the CI error; the guarded test passes under the same hammer
   - repeated normal runs pass
   
   Same caveat as #419 and #416: the full default goal hits the one 
pre-existing failure in 
`LocaleBeanificationTest.testContextClassloaderIndependence` on my machine, 
which fails identically on unmodified `1.X`; everything else passes.
   
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