@CheckReturnValue
    default SplitHttpRequest split(EventExecutor executor) {
        return new DefaultSplitHttpRequest(this, requireNonNull(executor, "executor"));
    }
Returns a new {@link SplitHttpRequest} which splits a stream of {@link HttpObject}s into
{@link HttpData}s and an HTTP trailers.
{@link SplitHttpRequest#trailers()} might not complete until the entire request body is consumed
completely.
core/src/main/java/com/linecorp/armeria/common/HttpRequest.java