code: @Override
      public void init() throws ServletException {
  
          String fedoraHome = Constants.FEDORA_HOME;
  
          if (fedoraHome == null || fedoraHome.length() == 0) {
              throw new ServletException("FEDORA_HOME is not defined");
          } else {
              _serverDir = new File(new File(fedoraHome), "server");
              if (!_serverDir.isDirectory()) {
                  throw new ServletException("No such directory: "
                          + _serverDir.getPath());
              }
          }
  
      }
docs: Initialize by setting serverDir based on FEDORA_HOME.