Module java.base
Package java.nio.channels

Interface CompletionHandler<V,​A>

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

    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 Details

    • completed

      void completed​(V result, A 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 exc, A 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.