CompletionHandler (Java Platform SE 8 ) (original) (raw)

• Type Parameters:
  V - The result type of the I/O operation
  A - The type of the object attached to the I/O operation

public interface CompletionHandler<V,A>
A handler for consuming the result of an asynchronous I/O operation.
The asynchronous channels defined in this package allow a completion handler to be specified to consume the result of an asynchronous operation. The completed method is invoked when the I/O operation completes successfully. The failed method is invoked if the I/O operations fails. The implementations of these methods should complete in a timely manner so as to avoid keeping the invoking thread from dispatching to other completion handlers.
Since:
1.7

• • Method Summary

  All Methods Instance Methods Abstract Methods

  Modifier and Type	Method	Description
  void	completed(V result,A attachment)	Invoked when an operation has completed.
  void	failed(Throwable exc,A attachment)	Invoked when an operation fails.

• • Method Detail

     * #### completed  
     void completed([V](../../../java/nio/channels/CompletionHandler.html "type parameter in CompletionHandler") result,  
                    [A](../../../java/nio/channels/CompletionHandler.html "type parameter in CompletionHandler") attachment)  
     Invoked when an operation has completed.  
     Parameters:  
     `result` \- The result of the I/O operation.  
     `attachment` \- The object attached to the I/O operation when it was initiated.  
     * #### failed  
     void failed([Throwable](../../../java/lang/Throwable.html "class in java.lang") exc,  
                 [A](../../../java/nio/channels/CompletionHandler.html "type parameter in CompletionHandler") attachment)  
     Invoked when an operation fails.  
     Parameters:  
     `exc` \- The exception to indicate why the I/O operation failed  
     `attachment` \- The object attached to the I/O operation when it was initiated.

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