code: static boolean getBooleanValFromVMArg(String vmArgValue, boolean defaultStateWhenNotDefined) {
          String sysProperty = System.getProperty(vmArgValue);
          boolean flag = defaultStateWhenNotDefined;
          if ((sysProperty != null) && (!sysProperty.isEmpty())) {
              flag = Boolean.parseBoolean(sysProperty);
          }
          return flag;
      }
docs: Returns boolean value of the JVM argument when defined, else returns the {@code defaultStateWhenNotDefined}.
  
  @param vmArgValue
  The VM argument name.
  @param defaultStateWhenNotDefined
  A boolean to indicate default state of the listener.