code: public void setupPropsForProxy(Props props, Props jobProps, final Logger logger)
        throws Exception {
      if (isProxyEnabled()) {
        userToProxy = jobProps.getString(HadoopSecurityManager.USER_TO_PROXY);
        logger.info("Need to proxy. Getting tokens.");
        // get tokens in to a file, and put the location in props
        tokenFile = HadoopJobUtils.getHadoopTokens(hadoopSecurityManager, props, logger);
        jobProps.put("env." + HADOOP_TOKEN_FILE_LOCATION, tokenFile.getAbsolutePath());
      }
    }
docs: Setup Job Properties when the proxy is enabled
  
  @param props all properties
  @param jobProps job properties
  @param logger logger handler