public String getMessage() {
    StringBuffer buf = new StringBuffer("Invalid constant name(s): ");
    if (getInvalidConstantNames() != null) {
      for (Iterator iter = invalidConstantNames.iterator(); iter.hasNext(); ) {
        buf.append("#$").append(iter.next());
        if (iter.hasNext()) {
          buf.append(", ");
        }
      }
    }
    return buf.toString();
  }