| layout | pattern | ||||
|---|---|---|---|---|---|
| title | Callback | ||||
| folder | callback | ||||
| permalink | /patterns/callback/ | ||||
| categories | Other | ||||
| tags |
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Intent: 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.
Applicability: 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] (http://docs.oracle.com/javase/7/docs/api/java/util/concurrent/CyclicBarrier.html#CyclicBarrier%28int,%20java.lang.Runnable%29) constructor can accept callback that will be triggered every time when barrier is tripped.