Rename various Proxy classes. Provide a Proxy interface.

corelib/src/promise.dart

 // Copyright (c) 2011, 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.
 
 // Dart core library.
 
 /** A promise to value of type [T] that may be computed asynchronously. */
 interface Promise<T> factory PromiseImpl<T> {
 
   Promise();
@@ skipping 72 matching lines @@
   void join(Collection<Promise<T>> arr, bool joinDone(Promise<T> completed));
 
   /**
    * Mark this promise as complete when [n] promises in [arr] complete, then
    * cancel the rest of the promises in [arr] that didn't complete.
    */
   void waitFor(Collection<Promise> arr, int n);
 }
 
 
-class Proxy extends ProxyImpl {
+interface Proxy factory ProxyImpl {
 
-  Proxy.forPort(SendPort port)
+  Proxy.forPort(SendPort port);
+  Proxy.forIsolate(Isolate isolate);
+  Proxy._forIsolateWithPromise(Isolate isolate, Promise<SendPort> promise);
+  /*
+   * The [Proxy.forReply] constructor is used to create a proxy for
+   * the object that will be the reply to a message send.
+   */
+  Proxy.forReply(Promise<SendPort> port);
+
+}
+
+
+class ProxyImpl extends ProxyBase implements Proxy {
+
+  ProxyImpl.forPort(SendPort port)
       : super.forPort(port) { }
 
-  Proxy.forIsolate(Isolate isolate)
+  ProxyImpl.forIsolate(Isolate isolate)
       : this._forIsolateWithPromise(isolate, new Promise<SendPort>());
 
-  Proxy._forIsolateWithPromise(Isolate isolate, Promise<SendPort> promise)
+  ProxyImpl._forIsolateWithPromise(Isolate isolate, Promise<SendPort> promise)
       // TODO(floitsch): it seems wrong to call super.forReply here.
       : super.forReply(promise) {
     isolate.spawn().then((SendPort port) {
       promise.complete(port);
     });
   }
 
   /*
    * The [Proxy.forReply] constructor is used to create a proxy for
    * the object that will be the reply to a message send.
    */
-  Proxy.forReply(Promise<SendPort> port)
+  ProxyImpl.forReply(Promise<SendPort> port)
       : super.forReply(port) { }
 
 }
 
 
 class Dispatcher<T> {
 
   Dispatcher(this.target) { }
 
   void _serve(ReceivePort port) {
     port.receive((var message, SendPort replyTo) {
       this.process(message, void reply(var response) {
         Proxy proxy = new Proxy.forPort(replyTo);
         proxy.send([response]);
       });
     });
   }
 
   static SendPort serve(Dispatcher dispatcher) {
-    ReceivePort port = ProxyImpl.register(dispatcher);
+    ReceivePort port = ProxyBase.register(dispatcher);
     dispatcher._serve(port);
     return port.toSendPort();
   }
 
   // BUG(5015671): DartC doesn't support 'abstract' yet.
   /* abstract */ void process(var message, void reply(var response)) {
     throw "Abstract method called";
   }
 
   T target;
 
 }
 
 // When a promise is sent across a port, it is converted to a
 // Promise<SendPort> down which we must send a port to receive the
 // completion value. Hand the Promise<SendPort> to this class to deal
 // with it.
 
 class PromiseProxy<T> extends PromiseImpl<T> {
   PromiseProxy(Promise<SendPort> sendCompleter) {
     ReceivePort completer = new ReceivePort.singleShot();
     completer.receive((var msg, SendPort _) {
       complete(msg[0]);
     });
     sendCompleter.addCompleteHandler((SendPort port) {
       port.send([completer.toSendPort()], null);
     });
   }
 }