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This idiom is also suitable for classes designed for inheritance. If a superclass thread requests a lock on the object's monitor, a subclass thread can interfere with its operation. For example, a subclass may use the superclass object's intrinsic lock for performing unrelated operations, causing significant lock contention and deadlock. Separating the locking strategy of the superclass from that of the subclass prevents ensures they do not share a common lock. It also permits fine-grained locking because multiple lock objects can be used for unrelated operations, increasing the overall responsiveness of the application.
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