code: DistributedFileSystem getDFS() throws IOException {
      if (this.dfs == null) {
        FileSystem fs = location.getDFS();
        if (!(fs instanceof DistributedFileSystem)) {
          ErrorMessageDialog.display("DFS Browser",
              "The DFS Browser cannot browse anything else "
                  + "but a Distributed File System!");
          throw new IOException("DFS Browser expects a DistributedFileSystem!");
        }
        this.dfs = (DistributedFileSystem) fs;
      }
      return this.dfs;
    }
docs: Gets a connection to the DFS
  
  @return a connection to the DFS
  @throws IOException