legacy/src/main/java/thredds/catalog/InvDataset.java
public String getRestrictAccess() {
    if (restrictAccess != null) return restrictAccess;
    // not found, look in parent
    if (parent != null)
      return parent.getRestrictAccess();

    return null;
  }
public String getRestrictAccess() {
    if (restrictAccess != null) return restrictAccess;
    // not found, look in parent
    if (parent != null)
      return parent.getRestrictAccess();

    return null;
  }
Return the resource control value which indicates that only users with
proper permission can access this resource.
<p/>
??? Not sure if the value indicates anything or just set or not set.

@return the resource control value for this dataset (inherited from ancestor datasets).