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Prefer using block synchronization instead of method synchronization when the method contains non-atomic operations that either do not require any synchronization or can use a more fine-grained locking scheme involving multiple internal private lock objects. Non-atomic operations can be decoupled from those that require synchronization and executed outside the synchronized block. The guideline CON04-J. Synchronize using an internal private final lock object has more details on using private internal lock objects and block synchronization.
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