Package org.pipecraft.pipes.async

Interface AsyncPipeListener<T>

  • Type Parameters:
    T - The data type the pipe works with
    public interface AsyncPipeListener<T>
    A listener to be attached to AsyncPipes. Gets notified in 3 cases: 1) When a pipe item is produced (analogous to a sync pipe returning some value when calling next()) 2) Upon successful termination (analogous to a sync pipe returning null in next() method) 3) Upon error termination (analogous to a sync pipe throwing an exception during call to next())
    Author:
    Eyal Schneider

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      void done()
      Indicates that the async pipe is done producing items, in a successfull manner.
      void error​(PipeException e)
      Notifies the listener that an error has been detected by the async pipe during item generation.
      void next​(T item)
      Notifies that a new item has been produced by the async pipe.

    • Method Detail

      • next

        void next​(T item)
   throws PipeException,
          InterruptedException
        Notifies that a new item has been produced by the async pipe. This method may be called by different threads, therefore should be implemented carefully. There's no guarantee regarding the order at which items are produced, and it may even be non-deterministic.
        Parameters:
        item - The produced item
        Throws:
        PipeException - In case that the new item should trigger a pipeline error
        InterruptedException - In case the thread is interrupted while handling the new item

      • done

        void done()
   throws InterruptedException
        Indicates that the async pipe is done producing items, in a successfull manner. This method is called at most once, and once called, it's guaranteed that no more calls to next(T) are expected. In addition, the implementation can assume that exactly one of error() / done() are called, but never both.
        Throws:
        InterruptedException - In case the thread is interrupted while handling the done event

      • error

        void error​(PipeException e)
    throws InterruptedException
        Notifies the listener that an error has been detected by the async pipe during item generation. The implementation can't assume that no further accept(..) calls will be made, but it can assume that exactly one of error() / done() are called, but never both.
        Parameters:
        e - The exception
        Throws:
        InterruptedException - In case the thread is interrupted while handling the done event