1// Copyright (c) 2009 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef CHROME_BROWSER_SYNC_ENGINE_SYNCER_COMMAND_H_
6#define CHROME_BROWSER_SYNC_ENGINE_SYNCER_COMMAND_H_
7#pragma once
8
9#include "base/basictypes.h"
10
11namespace browser_sync {
12
13namespace sessions {
14class SyncSession;
15}
16
17// Implementation of a simple command pattern intended to be driven by the
18// Syncer. SyncerCommand is abstract and all subclasses must implement
19// ExecuteImpl(). This is done so that chunks of syncer operation can be unit
20// tested.
21//
22// Example Usage:
23//
24//   SyncSession session = ...;
25//   SyncerCommand *cmd = SomeCommandFactory.createCommand(...);
26//   cmd->Execute(session);
27//   delete cmd;
28
29class SyncerCommand {
30 public:
31  SyncerCommand();
32  virtual ~SyncerCommand();
33
34  // Execute dispatches to a derived class's ExecuteImpl.
35  void Execute(sessions::SyncSession* session);
36
37  // ExecuteImpl is where derived classes actually do work.
38  virtual void ExecuteImpl(sessions::SyncSession* session) = 0;
39 private:
40  void SendNotifications(sessions::SyncSession* session);
41  DISALLOW_COPY_AND_ASSIGN(SyncerCommand);
42};
43
44}  // namespace browser_sync
45
46#endif  // CHROME_BROWSER_SYNC_ENGINE_SYNCER_COMMAND_H_
47