void HdfsClient::deleteInstance()
{
   ContextCli *currContext = GetCliGlobals()->currContext();
   HdfsClient *hdfsClient = currContext->getHDFSClient();
   if (hdfsClient != NULL) {
      NAHeap *heap = currContext->exHeap();
      NADELETE(hdfsClient, HdfsClient, heap);
      currContext->setHDFSClient(NULL);
   }
}
HdfsClient* HdfsClient::getInstance()
{
   ContextCli *currContext = GetCliGlobals()->currContext();
   HdfsClient *hdfsClient = currContext->getHDFSClient();
   HDFS_Client_RetCode retcode;
   if (hdfsClient == NULL) {
      NAHeap *heap = currContext->exHeap();
      hdfsClient = newInstance(heap, NULL, retcode);
      if (retcode != HDFS_CLIENT_OK)
         return NULL; 
      currContext->setHDFSClient(hdfsClient);
   }
   return hdfsClient;
}