Method ensure

future-java/src/main/java/io/trane/future/Promise.java:624–635

(final Runnable f)

  }

  @Override
  public final Future<T> ensure(final Runnable f) {
    if (getInterruptHandler() != null)
      return continuation(new Ensure<T>(f) {
        @Override
        protected final InterruptHandler getInterruptHandler() {
          return Promise.this;
        }
      });
    else
      return continuation(new Ensure<T>(f));
  }

  private static class OnSuccess<T> extends Continuation<T, T> {
    private final Consumer<? super T> c;