code: private boolean isWithinSubtree(X500Name other) {
          if (this == other) {
              return true;
          }
          if (other == null) {
              return false;
          }
          if (other.names.length == 0) {
              return true;
          }
          if (this.names.length == 0) {
              return false;
          }
          if (names.length < other.names.length) {
              return false;
          }
          for (int i = 0; i < other.names.length; i++) {
              if (!names[i].equals(other.names[i])) {
                  return false;
              }
          }
          return true;
      }
docs: Compares this name with another and determines if
  it is within the subtree of the other. Useful for
  checking against the name constraints extension.
  
  @return true iff this name is within the subtree of other.