UnaryPromiseNotifier Class — netty Architecture

Source Code

common/src/main/java/io/netty/util/concurrent/UnaryPromiseNotifier.java lines 26–56

@Deprecated
public final class UnaryPromiseNotifier<T> implements FutureListener<T> {
    private static final InternalLogger logger = InternalLoggerFactory.getInstance(UnaryPromiseNotifier.class);
    private final Promise<? super T> promise;

    public UnaryPromiseNotifier(Promise<? super T> promise) {
        this.promise = ObjectUtil.checkNotNull(promise, "promise");
    }

    @Override
    public void operationComplete(Future<T> future) throws Exception {
        cascadeTo(future, promise);
    }

    public static <X> void cascadeTo(Future<X> completedFuture, Promise<? super X> promise) {
        if (completedFuture.isSuccess()) {
            if (!promise.trySuccess(completedFuture.getNow())) {
                logger.warn("Failed to mark a promise as success because it is done already: {}", promise);
            }
        } else if (completedFuture.isCancelled()) {
            if (!promise.cancel(false)) {
                logger.warn("Failed to cancel a promise because it is done already: {}", promise);
            }
        } else {
            if (!promise.tryFailure(completedFuture.cause())) {
                logger.warn("Failed to mark a promise as failure because it's done already: {}", promise,
                            completedFuture.cause());
            }
        }
    }
}