code: public static boolean isSpecifiedPropertyName(final String propertyName) {
          boolean found = false;
          if (propertyName.startsWith(CUSTOM_PREFIX)) {
              return true;
          }
          if (propertyName.startsWith(EXTENSION_PREFIX)) {
              return true;
          }
          if (propertyName.startsWith(OAUTH_PREFIX)) {
              return true;
          }
          for (String key : BasicLTIConstants.validPropertyNames) {
              if (key.equals(propertyName)) {
                  found = true;
                  break;
              }
          }
          return found;
      }
docs: Checks to see if the passed propertyName is equal to one of the Strings
  contained in {@link BasicLTIConstants#validPropertyNames}. String
  matching is case sensitive.
  
  @param propertyName
  @return true if propertyName is equal to one of the Strings contained in
  {@link BasicLTIConstants#validPropertyNames} or is a custom parameter oe
  extension parameter ; else return false.