StreamConsumer has an addStream and a close functions.

sdk/lib/io/http_parser.dart

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 part of dart.io;
 
 // Global constants.
 class _Const {
   // Bytes for "HTTP".
   static const HTTP = const [72, 84, 84, 80];
@@ skipping 224 matching lines @@
     _socketSubscription = stream.listen(
         _onData,
         onError: _onError,
         onDone: () {
           _onDone();
           completer.complete(this);
         });
     return completer.future;
   }
 
+  Future<_HttpParser> addStream(Stream<List<int>> stream) {
+    throw new UnimplementedError("_HttpParser.addStream");
+  }
+
+  Future<_HttpParser> close() {
+    throw new UnimplementedError("_HttpParser.close");
+  }
+
   // From RFC 2616.
   // generic-message = start-line
   //                   *(message-header CRLF)
   //                   CRLF
   //                   [ message-body ]
   // start-line      = Request-Line | Status-Line
   // Request-Line    = Method SP Request-URI SP HTTP-Version CRLF
   // Status-Line     = HTTP-Version SP Status-Code SP Reason-Phrase CRLF
   // message-header  = field-name ":" [ field-value ]
   void _parse() {
@@ skipping 716 matching lines @@
   StreamController<_HttpIncoming> _controller;
   StreamController<List<int>> _bodyController;
 }
 
 
 class HttpParserException implements Exception {
   const HttpParserException([String this.message = ""]);
   String toString() => "HttpParserException: $message";
   final String message;
 }