1// Copyright (c) 2011 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_PREFS_PREF_VALUE_MAP_H_
6#define CHROME_BROWSER_PREFS_PREF_VALUE_MAP_H_
7#pragma once
8
9#include <map>
10#include <string>
11#include <vector>
12
13#include "base/basictypes.h"
14
15class Value;
16
17// A generic string to value map used by the PrefStore implementations.
18class PrefValueMap {
19 public:
20  typedef std::map<std::string, Value*>::iterator iterator;
21  typedef std::map<std::string, Value*>::const_iterator const_iterator;
22
23  PrefValueMap();
24  virtual ~PrefValueMap();
25
26  // Gets the value for |key| and stores it in |value|. Ownership remains with
27  // the map. Returns true if a value is present. If not, |value| is not
28  // touched.
29  bool GetValue(const std::string& key, const Value** value) const;
30  bool GetValue(const std::string& key, Value** value);
31
32  // Sets a new |value| for |key|. Takes ownership of |value|, which must be
33  // non-NULL. Returns true if the value changed.
34  bool SetValue(const std::string& key, Value* value);
35
36  // Removes the value for |key| from the map. Returns true if a value was
37  // removed.
38  bool RemoveValue(const std::string& key);
39
40  // Clears the map.
41  void Clear();
42
43  iterator begin();
44  iterator end();
45  const_iterator begin() const;
46  const_iterator end() const;
47
48  // Gets a boolean value for |key| and stores it in |value|. Returns true if
49  // the value was found and of the proper type.
50  bool GetBoolean(const std::string& key, bool* value) const;
51
52  // Gets a string value for |key| and stores it in |value|. Returns true if
53  // the value was found and of the proper type.
54  bool GetString(const std::string& key, std::string* value) const;
55
56  // Sets the value for |key| to the string |value|.
57  void SetString(const std::string& key, const std::string& value);
58
59  // Compares this value map against |other| and stores all key names that have
60  // different values in |differing_keys|. This includes keys that are present
61  // only in one of the maps.
62  void GetDifferingKeys(const PrefValueMap* other,
63                        std::vector<std::string>* differing_keys) const;
64
65 private:
66  typedef std::map<std::string, Value*> Map;
67
68  Map prefs_;
69
70  DISALLOW_COPY_AND_ASSIGN(PrefValueMap);
71};
72
73#endif  // CHROME_BROWSER_PREFS_PREF_VALUE_MAP_H_
74