code: public String findURIFromDoc(int owner)
    {
      int n = m_sourceTree.size();
  
      for (int i = 0; i < n; i++)
      {
        SourceTree sTree = (SourceTree) m_sourceTree.elementAt(i);
  
        if (owner == sTree.m_root)
          return sTree.m_url;
      }
  
      return null;
    }
docs: Given a document, find the URL associated with that document.
  @param owner Document that was previously processed by this liaison.
  
  @return The base URI of the owner argument.