Refactoring, moving and renaming the NetworkActionPredictor.

chrome/browser/predictors/predictor_database.h

+// Copyright (c) 2011 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 CHROME_BROWSER_PREDICTORS_PREDICTOR_DATABASE_H_
+#define CHROME_BROWSER_PREDICTORS_PREDICTOR_DATABASE_H_
+#pragma once
+
+#include <ostream>

[dominich, 2012/03/06 16:42:13]

why is ostream needed?

[Shishir, 2012/03/14 21:14:37]

From the earlier file. Removed.

+#include <string>
+#include <vector>
+
+#include "base/file_path.h"
+#include "base/memory/ref_counted.h"
+#include "base/string16.h"
+#include "base/synchronization/cancellation_flag.h"
+#include "chrome/browser/profiles/refcounted_profile_keyed_service.h"
+#include "googleurl/src/gurl.h"
+#include "sql/connection.h"
+
+class Profile;
+
+namespace predictors {
+
+// Refcounted as it is created and destroyed in the UI thread, but its database
+// related functions have to be called in the DB thread.
+class PredictorTableBase

[dominich, 2012/03/06 16:42:13]

Could be TableBase as we're in a namespace

[Shishir, 2012/03/14 21:14:37]

As we discussed, leaving as is. We want the names to be meaningful without the
namespaces.

+    : public base::RefCountedThreadSafe<PredictorTableBase> {
+ protected:
+  PredictorTableBase();
+  virtual ~PredictorTableBase();
+  virtual void CreateTableIfNonExistant() = 0;

[dominich, 2012/03/06 16:42:13]

nit: Existent

[Shishir, 2012/03/14 21:14:37]

Done.

+
+  sql::Connection* db_;
+  base::CancellationFlag cancelled_;
+
+ private:
+  friend class PredictorDatabase;
+  friend class base::RefCountedThreadSafe<PredictorTableBase>;
+
+  void SetCancelled();

[dominich, 2012/03/06 16:42:13]

note for dominic: it's a bit weird to have the flag protected and the setter
private.

[Shishir, 2012/03/14 21:14:37]

Yes, a little wierd, maybe move to protected?

+  void Initialize(sql::Connection* db);
+
+  DISALLOW_COPY_AND_ASSIGN(PredictorTableBase);
+};
+
+
+// This manages the autocomplete predictor table within the SQLite database
+// passed in to the constructor. It expects the following scheme:
+//
+// network_action_predictor
+//   id                 A unique id.
+//   user_text          What the user typed.
+//   url                The URL of the entry.
+//   number_of_hits     Number of times the entry was shown to the user and
+//                      selected.
+//   number_of_misses   Number of times the entry was shown to the user but not
+//                      selected.
+//
+// TODO(dominich): Consider adding this table to one of the history databases.
+// In memory is currently used, but adding to the on-disk visits database
+// would allow DeleteOldEntries to be cheaper through use of a join.
+class AutocompleteActionPredictorTable : public PredictorTableBase {

[dominich, 2012/03/06 16:42:13]

could drop 'Predictor' from the class name

[Shishir, 2012/03/14 21:14:37]

As discussed we want to keep this.

+ public:
+  struct Row {
+    // TODO(dominich): Make this 64-bit integer as an optimization. This
+    // requires some investigation into how to make sure the id is unique for
+    // each user_text/url pair.
+    // http://crbug.com/102020
+    typedef std::string Id;
+
+    Row();
+
+    // Only used by unit tests.
+    Row(const Id& id,
+        const string16& user_text,
+        const GURL& url,
+        int number_of_hits,
+        int number_of_misses);
+
+    Row(const Row& row);
+
+    Id id;
+    string16 user_text;
+    GURL url;
+    int number_of_hits;
+    int number_of_misses;
+  };
+
+  void GetRow(const Row::Id& id, Row* row);
+  void GetAllRows(std::vector<Row>* row_buffer);
+
+  void AddRow(const Row& row);
+  void UpdateRow(const Row& row);
+  void AddAndUpdateRows(const std::vector<Row>& rows_to_add,
+                        const std::vector<Row>& rows_to_update);
+  void DeleteRow(const Row::Id& id);
+  void DeleteRows(const std::vector<Row::Id>& id_list);
+  void DeleteAllRows();
+
+ private:
+  friend class PredictorDatabase;
+
+  AutocompleteActionPredictorTable();
+  virtual ~AutocompleteActionPredictorTable();
+
+  void CreateTableIfNonExistant() OVERRIDE;

[dominich, 2012/03/06 16:42:13]

nit: Existent

[Shishir, 2012/03/14 21:14:37]

Done.

+
+  bool StepAndInitializeRow(sql::Statement* statement, Row* row);
+  void BindRowToStatement(const Row& row, sql::Statement* statement);
+
+  DISALLOW_COPY_AND_ASSIGN(AutocompleteActionPredictorTable);
+};
+
+
+// RefcountedProfileKeyedService as it is created and destroyed on a different
+// thread to the DB thread that is required for all methods performing database
+// access.
+class PredictorDatabase : public RefcountedProfileKeyedService {

[dominich, 2012/03/06 16:42:13]

could drop 'Predictor' from name

[Shishir, 2012/03/14 21:14:37]

As we discussed, leaving as is. We want the names to be meaningful without the
namespaces.

+ public:
+  explicit PredictorDatabase(Profile* profile);
+  virtual ~PredictorDatabase();
+
+  // Opens the database file from the profile path. Separated from the
+  // constructor to ease construction/destruction of this object on one thread
+  // but database access on the DB thread.
+  void Initialize();
+
+  AutocompleteActionPredictorTable* autocomplete_table() {
+    return autocomplete_table_.get();
+  }
+
+ private:
+  friend class AutocompleteActionPredictorTableTest;
+
+  // RefcountedProfileKeyedService.
+  virtual void ShutdownOnUIThread() OVERRIDE;
+
+  FilePath db_path_;
+  sql::Connection db_;
+  scoped_refptr<AutocompleteActionPredictorTable> autocomplete_table_;
+
+  DISALLOW_COPY_AND_ASSIGN(PredictorDatabase);
+};
+
+}  // namespace predictors
+
+#endif  // CHROME_BROWSER_PREDICTORS_PREDICTOR_DATABASE_H_