code: protected String[] getPS() {
      ShellCommandExecutor shellExecutor = new ShellCommandExecutor(CMD);
      try {
        shellExecutor.execute();
      }
      catch (IOException e) {
        LOG.error(StringUtils.stringifyException(e));
        return null;
      }
      return shellExecutor.getOutput().split("\n");
    }
docs: Execute "ps -eo pid,ppid,pcpu,rss,command"
  @return String[] which contains the execution result