code: protected boolean isHadoopCluster() {
          boolean isHadoopCluster = false;
          try {
              isHadoopCluster = Shell.getHadoopHome() != null;
          } catch (IOException e) {
              // ignore - false is default setting
          }
          return isHadoopCluster;
      }
docs: Uses a hadoop shell to discern whether a hadoop cluster is available/configured.
  @return true if a hadoop cluster is detected.