Interface Observer<T>

  • Type Parameters:
    T - the type of item the Observer expects to observe

    public interface Observer<T>
    Provides a mechanism for receiving push-based notifications.

    After an Observer calls subscribe or subscribe method, the Connector calls the Observer's onNext(T) method to provide notifications. The Connector should call an Observer's onCompleted() or onError(java.lang.Throwable) method exactly once.

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      void onCompleted()
      Notifies the Observer that the Connector has finished sending push-based notifications.
      void onError​(java.lang.Throwable e)
      Notifies the Observer that the Connector has experienced an error condition.
      void onNext​(T t)
      Provides the Observer with a new item to observe.
    • Method Detail

      • onCompleted

        void onCompleted()
        Notifies the Observer that the Connector has finished sending push-based notifications.

        The Connector will not call this method if it calls onError(java.lang.Throwable).

      • onError

        void onError​(java.lang.Throwable e)
        Notifies the Observer that the Connector has experienced an error condition.

        If the Connector calls this method, it will not thereafter call onNext(T) or onCompleted().

        Parameters:
        e - the exception encountered by the Connector
      • onNext

        void onNext​(T t)
        Provides the Observer with a new item to observe.

        The Connector may call this method 0 or more times.

        The Connector will not call this method again after it calls either onCompleted() or onError(java.lang.Throwable).

        Parameters:
        t - the item emitted by the Connector