docs: protected boolean prevalidate(String component, BitSet disallowed) {
          // prevalidate the given component by disallowed characters
          if (component == null) {
              return false; // undefined
          }
          char[] target = component.toCharArray();
          for (int i = 0; i < target.length; i++) {
              if (disallowed.get(target[i])) {
                  return false;
              }
          }
          return true;
      }