code: public List<ODataHoleInfo> getHolesList() {
      acquireSharedLock();
      try {
  
        final List<ODataHoleInfo> holes = new ArrayList<ODataHoleInfo>();
  
        final int tot = holeSegment.getHoles();
        for (int i = 0; i < tot; ++i) {
          final ODataHoleInfo h = holeSegment.getHole(i);
          if (h != null)
            holes.add(h);
        }
  
        return holes;
  
      } finally {
        releaseSharedLock();
      }
    }
docs: Returns the list of holes as pair of position & ppos
  
  @throws IOException