@Override
    @UnstableApi
    public RequestOptionsBuilder responseTimeoutMode(ResponseTimeoutMode responseTimeoutMode) {
        this.responseTimeoutMode = requireNonNull(responseTimeoutMode, "responseTimeoutMode");
        return this;
    }
A builder for creating a new {@link RequestOptions}.
core/src/main/java/com/linecorp/armeria/client/RequestOptionsBuilder.java