Move the bits of Prefs where production code has only trivially easy

chrome/browser/api/prefs/pref_service_base.h

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-// This is the base interface for a preference services that provides
-// a way to access the application's current preferences.
-//
-// This base interface assumes all preferences are local.  See
-// SyncablePrefServiceBase for the interface to a preference service
-// that stores preferences that can be synced.
-//
-// Chromium settings and storage represent user-selected preferences and
-// information and MUST not be extracted, overwritten or modified except
-// through Chromium defined APIs.
-
-#ifndef CHROME_BROWSER_API_PREFS_PREF_SERVICE_BASE_H_
-#define CHROME_BROWSER_API_PREFS_PREF_SERVICE_BASE_H_
-
-#include "base/values.h"
-
-namespace content {
-class BrowserContext;
-class NotificationObserver;
-}
-
-namespace subtle {
-class PrefMemberBase;
-}
-
-class FilePath;
-class Profile;
-class TabContents;
-
-class PrefServiceBase {
- public:
-  // Retrieves a PrefServiceBase for the given context.
-  static PrefServiceBase* FromBrowserContext(content::BrowserContext* context);
-
-  virtual ~PrefServiceBase() {}
-
-  // Enum used when registering preferences to determine if it should be synced
-  // or not. This is only used for profile prefs, not local state prefs.
-  // See the Register*Pref methods for profile prefs below.
-  enum PrefSyncStatus {
-    UNSYNCABLE_PREF,
-    SYNCABLE_PREF
-  };
-
-  // Interface to a single preference.
-  class Preference {
-   public:
-    virtual ~Preference() {}
-
-    // Returns the name of the Preference (i.e., the key, e.g.,
-    // browser.window_placement).
-    virtual const std::string name() const = 0;
-
-    // Returns the registered type of the preference.
-    virtual base::Value::Type GetType() const = 0;
-
-    // Returns the value of the Preference, falling back to the registered
-    // default value if no other has been set.
-    virtual const base::Value* GetValue() const = 0;
-
-    // Returns the value recommended by the admin, if any.
-    virtual const base::Value* GetRecommendedValue() const = 0;
-
-    // Returns true if the Preference is managed, i.e. set by an admin policy.
-    // Since managed prefs have the highest priority, this also indicates
-    // whether the pref is actually being controlled by the policy setting.
-    virtual bool IsManaged() const = 0;
-
-    // Returns true if the Preference is recommended, i.e. set by an admin
-    // policy but the user is allowed to change it.
-    virtual bool IsRecommended() const = 0;
-
-    // Returns true if the Preference has a value set by an extension, even if
-    // that value is being overridden by a higher-priority source.
-    virtual bool HasExtensionSetting() const = 0;
-
-    // Returns true if the Preference has a user setting, even if that value is
-    // being overridden by a higher-priority source.
-    virtual bool HasUserSetting() const = 0;
-
-    // Returns true if the Preference value is currently being controlled by an
-    // extension, and not by any higher-priority source.
-    virtual bool IsExtensionControlled() const = 0;
-
-    // Returns true if the Preference value is currently being controlled by a
-    // user setting, and not by any higher-priority source.
-    virtual bool IsUserControlled() const = 0;
-
-    // Returns true if the Preference is currently using its default value,
-    // and has not been set by any higher-priority source (even with the same
-    // value).
-    virtual bool IsDefaultValue() const = 0;
-
-    // Returns true if the user can change the Preference value, which is the
-    // case if no higher-priority source than the user store controls the
-    // Preference.
-    virtual bool IsUserModifiable() const = 0;
-
-    // Returns true if an extension can change the Preference value, which is
-    // the case if no higher-priority source than the extension store controls
-    // the Preference.
-    virtual bool IsExtensionModifiable() const = 0;
-  };
-
-  // Returns true if the preference for the given preference name is available
-  // and is managed.
-  virtual bool IsManagedPreference(const char* pref_name) const = 0;
-
-  // Returns |true| if a preference with the given name is available and its
-  // value can be changed by the user.
-  virtual bool IsUserModifiablePreference(const char* pref_name) const = 0;
-
-  // Make the PrefService aware of a pref.
-  // TODO(zea): split local state and profile prefs into their own subclasses.
-  // ---------- Local state prefs  ----------
-  virtual void RegisterBooleanPref(const char* path,
-                                   bool default_value) = 0;
-  virtual void RegisterIntegerPref(const char* path,
-                                   int default_value) = 0;
-  virtual void RegisterDoublePref(const char* path,
-                                  double default_value) = 0;
-  virtual void RegisterStringPref(const char* path,
-                                  const std::string& default_value) = 0;
-  virtual void RegisterFilePathPref(const char* path,
-                                    const FilePath& default_value) = 0;
-  virtual void RegisterListPref(const char* path) = 0;
-  virtual void RegisterDictionaryPref(const char* path) = 0;
-  // These take ownership of the default_value:
-  virtual void RegisterListPref(const char* path,
-                                base::ListValue* default_value) = 0;
-  virtual void RegisterDictionaryPref(
-      const char* path, base::DictionaryValue* default_value) = 0;
-  // These variants use a default value from the locale dll instead.
-  virtual void RegisterLocalizedBooleanPref(
-      const char* path, int locale_default_message_id) = 0;
-  virtual void RegisterLocalizedIntegerPref(
-      const char* path, int locale_default_message_id) = 0;
-  virtual void RegisterLocalizedDoublePref(
-      const char* path, int locale_default_message_id) = 0;
-  virtual void RegisterLocalizedStringPref(
-      const char* path, int locale_default_message_id) = 0;
-  virtual void RegisterInt64Pref(const char* path,
-                                 int64 default_value) = 0;
-
-  //  ---------- Profile prefs  ----------
-  // Profile prefs must specify whether the pref should be synchronized across
-  // machines or not (see PrefSyncStatus enum above).
-  virtual void RegisterBooleanPref(const char* path,
-                                   bool default_value,
-                                   PrefSyncStatus sync_status) = 0;
-  virtual void RegisterIntegerPref(const char* path,
-                                   int default_value,
-                                   PrefSyncStatus sync_status) = 0;
-  virtual void RegisterDoublePref(const char* path,
-                                  double default_value,
-                                  PrefSyncStatus sync_status) = 0;
-  virtual void RegisterStringPref(const char* path,
-                                  const std::string& default_value,
-                                  PrefSyncStatus sync_status) = 0;
-  virtual void RegisterFilePathPref(const char* path,
-                                    const FilePath& default_value,
-                                    PrefSyncStatus sync_status) = 0;
-  virtual void RegisterListPref(const char* path,
-                                PrefSyncStatus sync_status) = 0;
-  virtual void RegisterDictionaryPref(const char* path,
-                                      PrefSyncStatus sync_status) = 0;
-  // These take ownership of the default_value:
-  virtual void RegisterListPref(const char* path,
-                                base::ListValue* default_value,
-                                PrefSyncStatus sync_status) = 0;
-  virtual void RegisterDictionaryPref(const char* path,
-                                      base::DictionaryValue* default_value,
-                                      PrefSyncStatus sync_status) = 0;
-  // These variants use a default value from the locale dll instead.
-  virtual void RegisterLocalizedBooleanPref(
-      const char* path,
-      int locale_default_message_id,
-      PrefSyncStatus sync_status) = 0;
-  virtual void RegisterLocalizedIntegerPref(
-      const char* path,
-      int locale_default_message_id,
-      PrefSyncStatus sync_status) = 0;
-  virtual void RegisterLocalizedDoublePref(
-      const char* path,
-      int locale_default_message_id,
-      PrefSyncStatus sync_status) = 0;
-  virtual void RegisterLocalizedStringPref(
-      const char* path,
-      int locale_default_message_id,
-      PrefSyncStatus sync_status) = 0;
-  virtual void RegisterInt64Pref(const char* path,
-                                 int64 default_value,
-                                 PrefSyncStatus sync_status) = 0;
-  virtual void RegisterUint64Pref(const char* path,
-                                  uint64 default_value,
-                                  PrefSyncStatus sync_status) = 0;
-  // Unregisters a preference.
-  virtual void UnregisterPreference(const char* path) = 0;
-
-  // Look up a preference.  Returns NULL if the preference is not
-  // registered.
-  virtual const Preference* FindPreference(const char* pref_name) const = 0;
-
-  // If the path is valid and the value at the end of the path matches the type
-  // specified, it will return the specified value.  Otherwise, the default
-  // value (set when the pref was registered) will be returned.
-  virtual bool GetBoolean(const char* path) const = 0;
-  virtual int GetInteger(const char* path) const = 0;
-  virtual double GetDouble(const char* path) const = 0;
-  virtual std::string GetString(const char* path) const = 0;
-  virtual FilePath GetFilePath(const char* path) const = 0;
-
-  // Returns the branch if it exists, or the registered default value otherwise.
-  // Note that |path| must point to a registered preference. In that case, these
-  // functions will never return NULL.
-  virtual const base::DictionaryValue* GetDictionary(
-      const char* path) const = 0;
-  virtual const base::ListValue* GetList(const char* path) const = 0;
-
-  // Removes a user pref and restores the pref to its default value.
-  virtual void ClearPref(const char* path) = 0;
-
-  // If the path is valid (i.e., registered), update the pref value in the user
-  // prefs.
-  // To set the value of dictionary or list values in the pref tree use
-  // Set(), but to modify the value of a dictionary or list use either
-  // ListPrefUpdate or DictionaryPrefUpdate from scoped_user_pref_update.h.
-  virtual void Set(const char* path, const base::Value& value) = 0;
-  virtual void SetBoolean(const char* path, bool value) = 0;
-  virtual void SetInteger(const char* path, int value) = 0;
-  virtual void SetDouble(const char* path, double value) = 0;
-  virtual void SetString(const char* path, const std::string& value) = 0;
-  virtual void SetFilePath(const char* path, const FilePath& value) = 0;
-
-  // Int64 helper methods that actually store the given value as a string.
-  // Note that if obtaining the named value via GetDictionary or GetList, the
-  // Value type will be TYPE_STRING.
-  virtual void SetInt64(const char* path, int64 value) = 0;
-  virtual int64 GetInt64(const char* path) const = 0;
-
-  // As above, but for unsigned values.
-  virtual void SetUint64(const char* path, uint64 value) = 0;
-  virtual uint64 GetUint64(const char* path) const = 0;
-
- protected:
-  // Registration of pref change observers must be done using the
-  // PrefChangeRegistrar, which is declared as a friend here to grant it
-  // access to the otherwise protected members Add/RemovePrefObserver.
-  // PrefMember registers for preferences changes notification directly to
-  // avoid the storage overhead of the registrar, so its base class must be
-  // declared as a friend, too.
-  friend class PrefChangeRegistrar;
-  friend class subtle::PrefMemberBase;
-
-  // These are protected so they can only be accessed by the friend
-  // classes listed above.
-  //
-  // If the pref at the given path changes, we call the observer's Observe
-  // method with PREF_CHANGED. Note that observers should not call these methods
-  // directly but rather use a PrefChangeRegistrar to make sure the observer
-  // gets cleaned up properly.
-  virtual void AddPrefObserver(const char* path,
-                               content::NotificationObserver* obs) = 0;
-  virtual void RemovePrefObserver(const char* path,
-                                  content::NotificationObserver* obs) = 0;
-};
-
-#endif  // CHROME_BROWSER_API_PREFS_PREF_SERVICE_BASE_H_