Interface Promise<C>

  • Type Parameters:
    C - the type of the result value
    All Known Implementing Classes:

    public interface Promise<C>

    The future result of an operation, either a value if the operation succeeded, or a failure if the operation failed.

    • Field Detail

      • NOOP

        static final Promise<?> NOOP

        Shared instance whose methods are implemented empty,

        use noop() to ease type inference.

    • Method Detail

      • succeed

        default void succeed​(C result)

        Callback to invoke when the operation succeeds.

        result - the result
        See Also:
      • fail

        default void fail​(Throwable failure)

        Callback to invoke when the operation fails.

        failure - the operation failure
      • complete

        default BiConsumer<C,​Throwable> complete()

        Returns a BiConsumer that, when invoked, completes this Promise.

        Typical usage is with CompletableFuture:

         public void process(ServerMessage message, Promise<Boolean> promise) {
             CompletableFuture.supplyAsync(() -> asyncOperation(message))
        a BiConsumer that completes this Promise
        See Also:
      • noop

        static <T> Promise<T> noop()
        Type Parameters:
        T - the type of the empty result
        a Promise whose methods are implemented empty.
      • from

        static <T> Promise<T> from​(Consumer<T> succeed,
                                   Consumer<Throwable> fail)
        Type Parameters:
        T - the type of the result value
        succeed - the Consumer to call in case of successful completion
        fail - the Consumer to call in case of failed completion
        a Promise from the given consumers
      • complete

        static <T> Promise<T> complete​(BiConsumer<T,​Throwable> fn)

        Returns a Promise that, when completed, invokes the given BiConsumer function.

        a Promise that invokes the BiConsumer