code: public boolean matchKey (final String key) {
          if (key == null) return false;
          for (int i = 0; i < values.length; ++i)
              if (values[i].equals(key)) return true;
          return false;
      }
docs: Returns <code>true</code> if one of the <i>keys</i> in the set equals the parameter.
  
  @param key the <i>key</i> to compare to the set's <i>keys</i>
  @return <code>true</code> if there is a match, <code>false</code> if there is not