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Difficulty-Beginner Functional Idiom Java Other


Callback is a piece of executable code that is passed as an argument to other code, which is expected to call back (execute) the argument at some convenient time.

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Use the Callback pattern when

  • when some arbitrary synchronous or asynchronous action must be performed after execution of some defined activity.

Real world examples

  • CyclicBarrier constructor can accept callback that will be triggered every time when barrier is tripped.