SingletonSupplier is not singleton if null is returned on first supplier call #35380
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| private static final Object NULL = new Object() { | ||
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| @Override | ||
| public String toString() { |
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It seems that overriding this method is not necessary, what's the purpose?
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The reason that the method is overridden isn't for functionality but for debugging purposes.
When overridden:
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 <[email protected]>
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See #35369