code: private void printConfigInfo(SparkConf conf, PrintWriter reportWriter) {
      // Get Spark configurations
      if (conf.contains("spark.master")) {
        reportWriter.printf("Spark master is: %s.%n%n", conf.get("spark.master"));
      }
      if (conf.contains("spark.submit.deployMode")) {
        reportWriter.printf("spark-submit deploy mode is: %s.%n%n",
            conf.get("spark.submit.deployMode"));
      }
      if (conf.contains("spark.driver.extraClassPath")) {
        reportWriter.printf("spark.driver.extraClassPath includes jar paths: %s.%n%n",
            conf.get("spark.driver.extraClassPath"));
      }
      if (conf.contains("spark.executor.extraClassPath")) {
        reportWriter.printf("spark.executor.extraClassPath includes jar paths: %s.%n%n",
            conf.get("spark.executor.extraClassPath"));
      }
    }
docs: Saves related Spark and Alluxio configuration information.
  
  @param conf the current SparkConf
  @param reportWriter save user-facing messages to a generated file