@Override
 public String getNextInner() {
   String next = null;
   if (slr != null) {
     try {
       next = slr.readLine();
     } catch (IOException e) {
       e.printStackTrace();
       throw new RuntimeException(e);
     }
   }
   return next;
 }
 @Override
 public void close() throws IOException {
   slr.close();
 }