code: protected String getSitePath(String uri) {
  
          if (m_internal) {
              String siteRoot = getSiteRoot();
              if (siteRoot != null) {
                  return uri.substring(siteRoot.length());
              } else {
                  return uri;
              }
          }
          return null;
      }
docs: Helper method for getting the site path for a uri.<p>
  
  @param uri a VFS uri
  @return the site path