code: public static HadoopSecurityManager loadHadoopSecurityManager(Props props, Logger log)
        throws RuntimeException {
  
      Class<?> hadoopSecurityManagerClass = props.getClass(HADOOP_SECURITY_MANAGER_CLASS_PARAM, true,
          HadoopJobUtils.class.getClassLoader());
      log.info("Loading hadoop security manager " + hadoopSecurityManagerClass.getName());
      HadoopSecurityManager hadoopSecurityManager = null;
  
      try {
        Method getInstanceMethod = hadoopSecurityManagerClass.getMethod("getInstance", Props.class);
        hadoopSecurityManager = (HadoopSecurityManager) getInstanceMethod.invoke(
            hadoopSecurityManagerClass, props);
      } catch (InvocationTargetException e) {
        String errMsg = "Could not instantiate Hadoop Security Manager "
            + hadoopSecurityManagerClass.getName() + e.getCause();
        log.error(errMsg);
        throw new RuntimeException(errMsg, e);
      } catch (Exception e) {
        throw new RuntimeException(e);
      }
  
      return hadoopSecurityManager;
    }
docs: Based on the HADOOP_SECURITY_MANAGER_CLASS_PARAM setting in the incoming props, finds the
  correct HadoopSecurityManager Java class
  
  @return a HadoopSecurityManager object. Will throw exception if any errors occur (including not
  finding a class)
  @throws RuntimeException : If any errors happen along the way.