#vulnerable code 
                              @Override
  public void setException(Exception exception) {
    rowObserver.onError(exception);
    // cleanup any state that was in RowMerger. There may be a partial row in progress which needs
    // to be reset.
    rowMerger = new RowMerger(rowObserver);
    super.setException(exception);
  } 
                            #location 6 
                            #vulnerability type THREAD_SAFETY_VIOLATION
#fixed code
                              @Override
  public void setException(Exception exception) {
    rowMerger.onError(exception);
    super.setException(exception);
  }