Remane io_stream_consumer.dart to io_sink and move out all implementation from IOSink to _IOSinkImp…

sdk/lib/io/io_sink.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;
 
 /**
  * Helper class to wrap a [StreamConsumer<List<int>, T>] and provide utility
  * functions for writing to the StreamConsumer directly. The [IOSink]
  * buffers the input given by [add] and [addString] and will delay a [consume]
  * or [addStream] until the buffer is flushed.
  *
  * When the [IOSink] is bound to a stream (through either [consume]
  * or [addStream]) any call to the [IOSink] will throw a
  * [StateError].
  */
-class IOSink<T> implements StreamConsumer<List<int>, T> {
+abstract class IOSink<T> implements StreamConsumer<List<int>, T> {
+  factory IOSink(StreamConsumer<List<int>, T> target)
+      => new _IOSinkImpl(target);
+
+  /**
+   * Provide functionality for piping to the [IOSink].
+   */
+  Future<T> consume(Stream<List<int>> stream);
+
+  /**
+   * Like [consume], but will not close the target when done.
+   */
+  Future<T> addStream(Stream<List<int>> stream);
+
+  /**
+   * Write a list of bytes to the target.
+   */
+  void add(List<int> data);
+
+  /**
+   * Write a String to the target.
+   */
+  void addString(String string, [Encoding encoding = Encoding.UTF_8]);
+
+  /**
+   * Close the target.
+   */
+  void close();
+
+  /**
+   * Get future that will complete when all data has been written to
+   * the IOSink and it has been closed.
+   */
+  Future<T> get done;
+}
+
+
+class _IOSinkImpl<T> implements IOSink<T> {
   final StreamConsumer<List<int>, T> _target;
 
   StreamController<List<int>> _controllerInstance;
   Future<T> _pipeFuture;
   StreamSubscription<List<int>> _bindSubscription;
   bool _paused = true;
 
-  IOSink(StreamConsumer<List<int>, T> target) : _target = target;
+  _IOSinkImpl(StreamConsumer<List<int>, T> target) : _target = target;
 
-  /**
-   * Provide functionality for piping to the [IOSink].
-   */
   Future<T> consume(Stream<List<int>> stream) {
     if (_isBound) {
       throw new StateError("IOSink is already bound to a stream");
     }
     return _fillFromStream(stream);
   }
 
-  /**
-   * Like [consume], but will not close the target when done.
-   */
   Future<T> addStream(Stream<List<int>> stream) {
     if (_isBound) {
       throw new StateError("IOSink is already bound to a stream");
     }
     return _fillFromStream(stream, unbind: true);
   }
 
-  /**
-   * Write a list of bytes to the target.
-   */
   void add(List<int> data) {
     if (_isBound) {
       throw new StateError("IOSink is already bound to a stream");
     }
     _controller.add(data);
   }
 
-  /**
-   * Write a String to the target.
-   */
   void addString(String string, [Encoding encoding = Encoding.UTF_8]) {
     add(_encodeString(string, encoding));
   }
 
-  /**
-   * Close the target.
-   */
   void close() {
     if (_isBound) {
       throw new StateError("IOSink is already bound to a stream");
     }
     _controller.close();
   }
 
-  /**
-   * Get future that will complete when all data has been written to
-   * the IOSink and it has been closed.
-   */
   Future<T> get done {
     _controller;
     return _pipeFuture.then((_) => this);
   }
 
   StreamController<List<int>> get _controller {
     if (_controllerInstance == null) {
       _controllerInstance = new StreamController<List<int>>(
           onPauseStateChange: _onPauseStateChange,
           onSubscriptionStateChange: _onSubscriptionStateChange);
@@ skipping 76 matching lines @@
     if (unbind) {
       _pipeFuture
           .then((_) => completeUnbind(),
                 onError: (error) => completeUnbind(error));
       return unbindCompleter.future;
     } else {
       return _pipeFuture.then((_) => this);
     }
   }
 }