private static final ObjectAllocator HTML_SAXPARSER_CONTEXT_ALLOCATOR = new ObjectAllocator()
  {
    private Html4SaxParserContext htmlSaxParserContext = null;
    public IRubyObject allocate(Ruby runtime, RubyClass klazz) {
      if (htmlSaxParserContext == null) { htmlSaxParserContext = new Html4SaxParserContext(runtime, klazz); }