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This idiom can also be suitably used by classes designed for inheritance. If a superclass thread requests a lock on the class object's monitor, a subclass thread can interfere with its operation. Refer to the guideline CON02-J. Always synchronize on the appropriate object for more details.
This idiom is only useful for objects that may be accessible to hostile code. A private object gains no benefits from synchronizing on a private lock object, rather than synchronizing on its own intrinsic lock.
Noncompliant Code Example
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