#vulnerable code 
                              public void close() {
    if (_zkClient != null) {
      _zkClient.close();
    }
    if (_zkMetadataStoreDirectory != null) {
      _zkMetadataStoreDirectory.close();
    }
    if (_zkClientForListener != null) {
      _zkClientForListener.close();
    }
  } 
                            #location 9 
                            #vulnerability type THREAD_SAFETY_VIOLATION
#fixed code
                              public void close() {
    if (_zkClient != null) {
      _zkClient.close();
    }
    if (_zkMetadataStoreDirectory != null) {
      _zkMetadataStoreDirectory.close();
    }
    if (_zkClientForRoutingDataListener != null) {
      _zkClientForRoutingDataListener.close();
    }
  }