legacy/src/main/java/thredds/catalog/InvDataset.java
public String getUniqueID() {
    String authority = getAuthority();
    if ((authority != null) && (getID() != null))
      return authority + ":" + getID();
    else if (getID() != null)
      return getID();
    else
      return null;
  }
public String getUniqueID() {
    String authority = getAuthority();
    if ((authority != null) && (getID() != null))
      return authority + ":" + getID();
    else if (getID() != null)
      return getID();
    else
      return null;
  }
If this dataset has an authority and an ID, then the concatenation of them is the
globally unique ID.

@return globally unique ID, or null if missing authority or ID.