Introduce a layering in the invalidation component as public and impl

components/invalidation/invalidator_registrar.h

-// Copyright 2014 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.
-
-#ifndef COMPONENTS_INVALIDATION_INVALIDATOR_REGISTRAR_H_
-#define COMPONENTS_INVALIDATION_INVALIDATOR_REGISTRAR_H_
-
-#include <map>
-
-#include "base/basictypes.h"
-#include "base/observer_list.h"
-#include "base/threading/thread_checker.h"
-#include "components/invalidation/invalidation_export.h"
-#include "components/invalidation/invalidation_handler.h"
-#include "components/invalidation/invalidation_util.h"
-
-namespace invalidation {
-class ObjectId;
-}  // namespace invalidation
-
-namespace syncer {
-
-class ObjectIdInvalidationMap;
-
-// A helper class for implementations of the Invalidator interface.  It helps
-// keep track of registered handlers and which object ID registrations are
-// associated with which handlers, so implementors can just reuse the logic
-// here to dispatch invalidations and other interesting notifications.
-class INVALIDATION_EXPORT InvalidatorRegistrar {
- public:
-  InvalidatorRegistrar();
-
-  // It is an error to have registered handlers on destruction.
-  ~InvalidatorRegistrar();
-
-  // Starts sending notifications to |handler|.  |handler| must not be NULL,
-  // and it must already be registered.
-  void RegisterHandler(InvalidationHandler* handler);
-
-  // Updates the set of ObjectIds associated with |handler|.  |handler| must
-  // not be NULL, and must already be registered.  An ID must be registered for
-  // at most one handler. If ID is already registered function returns false.
-  bool UpdateRegisteredIds(InvalidationHandler* handler,
-                           const ObjectIdSet& ids) WARN_UNUSED_RESULT;
-
-  // Stops sending notifications to |handler|.  |handler| must not be NULL, and
-  // it must already be registered.  Note that this doesn't unregister the IDs
-  // associated with |handler|.
-  void UnregisterHandler(InvalidationHandler* handler);
-
-  ObjectIdSet GetRegisteredIds(InvalidationHandler* handler) const;
-
-  // Returns the set of all IDs that are registered to some handler (even
-  // handlers that have been unregistered).
-  ObjectIdSet GetAllRegisteredIds() const;
-
-  // Sorts incoming invalidations into a bucket for each handler and then
-  // dispatches the batched invalidations to the corresponding handler.
-  // Invalidations for IDs with no corresponding handler are dropped, as are
-  // invalidations for handlers that are not added.
-  void DispatchInvalidationsToHandlers(
-      const ObjectIdInvalidationMap& invalidation_map);
-
-  // Updates the invalidator state to the given one and then notifies
-  // all handlers.  Note that the order is important; handlers that
-  // call GetInvalidatorState() when notified will see the new state.
-  void UpdateInvalidatorState(InvalidatorState state);
-
-  // Returns the current invalidator state.  When called from within
-  // InvalidationHandler::OnInvalidatorStateChange(), this returns the
-  // updated state.
-  InvalidatorState GetInvalidatorState() const;
-
-  // Gets a new map for the name of invalidator handlers and their
-  // objects id. This is used by the InvalidatorLogger to be able
-  // to display every registered handlers and its objectsIds.
-  std::map<std::string, ObjectIdSet> GetSanitizedHandlersIdsMap();
-
-  bool IsHandlerRegisteredForTest(const InvalidationHandler* handler) const;
-
-  // Needed for death tests.
-  void DetachFromThreadForTest();
-
- private:
-  typedef std::map<InvalidationHandler*, ObjectIdSet> HandlerIdsMap;
-
-  base::ThreadChecker thread_checker_;
-  base::ObserverList<InvalidationHandler, true> handlers_;
-  HandlerIdsMap handler_to_ids_map_;
-  InvalidatorState state_;
-
-  DISALLOW_COPY_AND_ASSIGN(InvalidatorRegistrar);
-};
-
-}  // namespace syncer
-
-#endif  // COMPONENTS_INVALIDATION_INVALIDATOR_REGISTRAR_H_