code: public int namespaceIndex(String namespace, Vector extensions)
    {
      for (int i = 0; i < extensions.size(); i++)
      {
        if (((ExtensionNamespaceSupport)extensions.get(i)).getNamespace().equals(namespace))
          return i;
      }
      return -1;
    }
docs: Get the index for a namespace entry in the extension namespace Vector, -1 if
  no such entry yet exists.