SingletonSupplier is not singleton if null is returned on first supplier call #35380
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spring-projects-issues added the status: waiting-for-triage 
nosan force-pushed the 35369 branch 2 times, most recently from a722667 to a596879 Compare 
quaff reviewed Aug 25, 2025
spring-core/src/main/java/org/springframework/util/function/SingletonSupplier.java Outdated Show resolved Hide resolved
Previously, SingletonSupplier stored "null" in singletonInstance when the supplied instance was "null". On subsequent get() calls, this was treated as "uninitialized" and triggered another attempt to obtain an instance. This commit ensures that a "null" returned from the instanceSupplier or defaultSupplier is handled correctly, so that subsequent calls to get() return "null" consistently instead of repeatedly invoking the supplier. Signed-off-by: Dmytro Nosan <dimanosan@gmail.com>
.../src/test/java/org/springframework/jdbc/support/SQLErrorCodeSQLExceptionTranslatorTests.java Show resolved Hide resolved
spring-core/src/main/java/org/springframework/util/function/SingletonSupplier.java Show resolved Hide resolved
sbrannen added in: core sbrannen changed the title SingletonSupplier is not singleton if null is returned on first supplier call sbrannen added a commit that referenced this pull request Oct 30, 2025
| Thanks, @sbrannen! |
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See #35369