chrome/browser/predictors componentization part-1

chrome/browser/predictors/predictor_database.h

Index: chrome/browser/predictors/predictor_database.h
diff --git a/chrome/browser/predictors/predictor_database.h b/chrome/browser/predictors/predictor_database.h
index 1692e3390dbf4049ddaf3b643bb50f832ac4ca4b..9cb13b5487c9b1feb48eac654812761079cc38aa 100644
--- a/chrome/browser/predictors/predictor_database.h
+++ b/chrome/browser/predictors/predictor_database.h
@@ -5,11 +5,11 @@
 #ifndef CHROME_BROWSER_PREDICTORS_PREDICTOR_DATABASE_H_
 #define CHROME_BROWSER_PREDICTORS_PREDICTOR_DATABASE_H_
 
+#include "base/file_path.h"
 #include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
 #include "chrome/browser/profiles/profile_keyed_service.h"
 
-class Profile;
-
 namespace sql {
 class Connection;
 }
@@ -20,22 +20,41 @@ class AutocompleteActionPredictorTable;
 class PredictorDatabaseInternal;
 class ResourcePrefetchPredictorTables;
 
-class PredictorDatabase : public ProfileKeyedService {
+// Refcounted as it is created, initialized and destroyed on a different thread
+// to the DB thread that is required for all methods performing database access.
+class PredictorDatabase
+    : public base::RefCountedThreadSafe<PredictorDatabase> {
  public:
-  explicit PredictorDatabase(Profile* profile);
+  explicit PredictorDatabase(const FilePath& path,
+                             bool is_resource_prefetch_predictor_enabled);
   virtual ~PredictorDatabase();
 
   scoped_refptr<AutocompleteActionPredictorTable> autocomplete_table();
   scoped_refptr<ResourcePrefetchPredictorTables> resource_prefetch_tables();
 
+  // Cancels pending DB transactions. Should only be called on the UI thread.
+  void SetCancelled();
+
   // Used for testing.
   sql::Connection* GetDatabase();
 
  private:
-  // ProfileKeyedService
-  virtual void Shutdown() OVERRIDE;
+  friend class base::RefCountedThreadSafe<PredictorDatabase>;
+
+  // Opens the database file. Separated from the constructor to ease
+  // construction/destruction of this object on one thread but database access
+  // on the DB thread.
+  void Initialize();
+  void LogDatabaseStats();  //  DB Thread.
+
+  FilePath db_path_;
+  bool is_resource_prefetch_predictor_enabled_;
+  scoped_ptr<sql::Connection> db_;
 
-  scoped_refptr<PredictorDatabaseInternal> db_;
+  // TODO(shishir): These tables may not need to be refcounted. Maybe move them
+  // to using a WeakPtr instead.
+  scoped_refptr<AutocompleteActionPredictorTable> autocomplete_table_;
+  scoped_refptr<ResourcePrefetchPredictorTables> resource_prefetch_tables_;
 
   DISALLOW_COPY_AND_ASSIGN(PredictorDatabase);
 };