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The @ThreadSafe annotation is applied to a class to indicate that it is thread-safe. This means that no sequences of accesses (reads and writes to public fields, calls to public methods) can leave the object in an inconsistent state, regardless of the interleaving of these accesses by the runtime or any external synchronization or coordination on the part of the caller.
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The @Immutable annotation is applied to immutable classes. Immutable objects are inherently thread-safe; once they are fully constructed, they may be published via a reference and shared safely among multiple threads.
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