public static HeaderOverridingHttpRequest of(HttpRequest delegate, RequestHeaders headers) {
        requireNonNull(delegate, "delegate");
        requireNonNull(headers, "headers");
        if (delegate instanceof HeaderOverridingHttpRequest) {
            return new HeaderOverridingHttpRequest(
                    ((HeaderOverridingHttpRequest) delegate).delegate(), headers);
        }
        return new HeaderOverridingHttpRequest(delegate, headers);
    }
An {@link HttpRequest} that overrides the {@link RequestHeaders}.
core/src/main/java/com/linecorp/armeria/internal/common/HeaderOverridingHttpRequest.java