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For instance, consider a scenario where the standard thread-safe API does not provide a method to both find a particular person's record in a Hashtable and also update the corresponding payroll information. In such cases, a custom atomic method must be designed and used. This guideline discusses the rationale behind using such a method and provides the relevant implementation advice.
Enumerations and iterators of objects of a Collection and iterators also require explicit synchronization on the Collection object (client-side locking) or an internal private lock object.
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