_resolver = resolver;
_resolver = artresolver;
    public ResolvedModuleRevisionProxy(ResolvedModuleRevision mr, DependencyResolver resolver) {        if (mr == null) {            throw new NullPointerException("null module revision not allowed");        }        if (resolver == null) {            throw new NullPointerException("null resolver not allowed");        }        _mr = mr;        _resolver = resolver;    }