Add ASM metadata reader fallback and slim ClassFile method metadata - #36978
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LordKay-sudo wants to merge 1 commit into
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Allow -Dspring.classformat.metadatareader.asm=true to use the ASM-based SimpleMetadataReaderFactory on Java 24+ as a workaround for high memory use of ClassFileAnnotationMetadata (spring-projectsgh-36737). Reduce retained memory per method by storing ASM-style int access flags and descriptor strings instead of ClassFile API type objects. Related to spring-projectsgh-36737 Signed-off-by: LordKay-sudo <lkandiro@gmail.com>
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Thanks for the proposal, but I don't think we can accept this: this introduces a dependency on ASM in the ClassFile implementation. The entire goal here is to not rely on ASM for class metadata introspection. |
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Summary
Addresses bclozel's issue 2 and the ASM workaround discussed in gh-36737:
-Dspring.classformat.metadatareader.asm=trueto select the ASM-basedSimpleMetadataReaderFactoryon Java 24+ (official alternative to shadowingMetadataReaderFactoryDelegate)ClassFileMethodMetadataby storing int access flags and JVM descriptor strings instead ofAccessFlags/MethodTypeDescobjectsContext
Several reporters (@bherczyk, @lbenedetto, @pkernevez) resolved OOM by switching back to ASM metadata reading. This provides a supported configuration flag for that workaround while ClassFile memory use is further optimized.
Test plan
./gradlew :spring-core:test --tests "org.springframework.core.type.classreading.*"./gradlew :spring-core:test --tests "org.springframework.core.type.classreading.MetadataReaderFactoryDelegateTests"Related to gh-36737