static {
   specialClasses.put("org.apache.spark.repl.Main", "spark-shell");
   specialClasses.put(
       "org.apache.spark.sql.hive.thriftserver.SparkSQLCLIDriver", "spark-internal");
   specialClasses.put(
       "org.apache.spark.sql.hive.thriftserver.HiveThriftServer2", "spark-internal");
 }
  private void constructEnvVarArgs(Map<String, String> env, String submitArgsEnvVariable)
      throws IOException {
    mergeEnvPathList(
        env,
        getLibPathEnvName(),
        getEffectiveConfig().get(SparkLauncher.DRIVER_EXTRA_LIBRARY_PATH));

    StringBuilder submitArgs = new StringBuilder();
    for (String arg : buildSparkSubmitArgs()) {
      if (submitArgs.length() > 0) {
        submitArgs.append(" ");
      }
      submitArgs.append(quoteForCommandString(arg));
    }
    env.put(submitArgsEnvVariable, submitArgs.toString());
  }
  private List<String> buildSparkRCommand(Map<String, String> env) throws IOException {
    if (!appArgs.isEmpty() && appArgs.get(0).endsWith(".R")) {
      System.err.println(
          "Running R applications through 'sparkR' is not supported as of Spark 2.0.\n"
              + "Use ./bin/spark-submit <R file>");
      System.exit(-1);
    }
    // When launching the SparkR shell, store the spark-submit arguments in the SPARKR_SUBMIT_ARGS
    // env variable.
    constructEnvVarArgs(env, "SPARKR_SUBMIT_ARGS");

    // Set shell.R as R_PROFILE_USER to load the SparkR package when the shell comes up.
    String sparkHome = System.getenv("SPARK_HOME");
    env.put(
        "R_PROFILE_USER",
        join(File.separator, sparkHome, "R", "lib", "SparkR", "profile", "shell.R"));

    List<String> args = new ArrayList<>();
    args.add(firstNonEmpty(System.getenv("SPARKR_DRIVER_R"), "R"));
    return args;
  }