asmhatre
66208bcd97
A Spring Boot 4.1.1 module whose test suite is the evidence for the article: 19 tests producing 22 transcripts under docs/output/, plus 12 documentation chapters. Findings the build pins: - @EnableCaching has no exposeProxy attribute; the widely-copied @EnableCaching(exposeProxy = true) does not compile. - Two methods sharing a cache name and an argument type share a key space, and one silently serves the other's answers. - beforeInvocation = true is NOT deferred by TransactionAwareCacheManagerProxy on 7.0.9 - doEvict picks evictIfPresent, which the decorator does not intercept. - Four of five invalid declarations start a clean context and throw at the first call. - Caffeine on the classpath silently displaces the simple provider.
26 lines
1.2 KiB
Plaintext
26 lines
1.2 KiB
Plaintext
# TransactionAwareCacheManagerProxy, and what it does not cover
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cacheManager : org.springframework.cache.transaction.TransactionAwareCacheManagerProxy
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nameOf(1) -> Alice
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after the identical rollback, nameOf(1) -> Alice
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The put was registered as a transaction synchronisation and dropped when the
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transaction rolled back instead of committing.
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--- what it does not cover: beforeInvocation = true ---
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inside the same transaction, after an evict declared beforeInvocation=true,
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a re-read returns : Bobby
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Not the stale value. The eviction was NOT deferred, and the re-read went to
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the database and saw the uncommitted row. The reason is in the bytecode:
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AbstractCacheInvoker.doEvict(cache, key, immediate) calls evictIfPresent()
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when immediate is true and evict() when it is false, and the decorator only
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registers a post-commit synchronisation in evict() - evictIfPresent()
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delegates straight to the target cache. See docs/output/22-decorator-bytecode.txt.
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Two gaps do remain, and they are structural rather than measurable here:
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reads are never deferred, so a @Cacheable lookup inside the transaction sees
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whatever the shared cache holds; and outside a transaction the proxy is a
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pass-through that writes immediately.
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