Refactoring AutocompleteActionPredictor Database.

chrome/browser/predictors/autocomplete_action_predictor_table.cc

Index: chrome/browser/predictors/autocomplete_action_predictor_table.cc
diff --git a/chrome/browser/predictors/autocomplete_action_predictor_table.cc b/chrome/browser/predictors/autocomplete_action_predictor_table.cc
new file mode 100644
index 0000000000000000000000000000000000000000..0e3a5d4b340bc29cc37d3cff83a39882f1383884
--- /dev/null
+++ b/chrome/browser/predictors/autocomplete_action_predictor_table.cc
@@ -0,0 +1,242 @@
+// 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.
+
+#include "chrome/browser/predictors/autocomplete_action_predictor_table.h"
+
+#include "base/logging.h"
+#include "base/metrics/histogram.h"
+#include "base/stringprintf.h"
+#include "base/utf_string_conversions.h"
+#include "chrome/common/guid.h"
+#include "content/public/browser/browser_thread.h"
+#include "sql/statement.h"
+
+namespace {
+
+// TODO(shishir): Rename the table for consistency.
+const char kAutocompletePredictorTableName[] = "network_action_predictor";
+
+// The maximum length allowed for strings in the database.
+const size_t kMaxDataLength = 2048;
+
+void BindRowToStatement(
+    const predictors::AutocompleteActionPredictorTable::Row& row,
+    sql::Statement* statement) {
+  DCHECK(guid::IsValidGUID(row.id));
+  statement->BindString(0, row.id);
+  statement->BindString16(1, row.user_text.substr(0, kMaxDataLength));
+  statement->BindString(2, row.url.spec().substr(0, kMaxDataLength));
+  statement->BindInt(3, row.number_of_hits);
+  statement->BindInt(4, row.number_of_misses);
+}
+
+bool StepAndInitializeRow(
+    sql::Statement* statement,
+    predictors::AutocompleteActionPredictorTable::Row* row) {
+  if (!statement->Step())
+    return false;
+
+  row->id = statement->ColumnString(0);
+  row->user_text = statement->ColumnString16(1);
+  row->url = GURL(statement->ColumnString(2));
+  row->number_of_hits = statement->ColumnInt(3);
+  row->number_of_misses = statement->ColumnInt(4);
+  return true;
+}
+
+}  // namespace
+
+namespace predictors {
+
+AutocompleteActionPredictorTable::Row::Row()
+    : number_of_hits(0),
+      number_of_misses(0) {
+}
+
+AutocompleteActionPredictorTable::Row::Row(const Row::Id& id,
+                                           const string16& user_text,
+                                           const GURL& url,
+                                           int number_of_hits,
+                                           int number_of_misses)
+    : id(id),
+      user_text(user_text),
+      url(url),
+      number_of_hits(number_of_hits),
+      number_of_misses(number_of_misses) {
+}
+
+AutocompleteActionPredictorTable::Row::Row(const Row& row)
+    : id(row.id),
+      user_text(row.user_text),
+      url(row.url),
+      number_of_hits(row.number_of_hits),
+      number_of_misses(row.number_of_misses) {
+}
+
+
+void AutocompleteActionPredictorTable::GetRow(const Row::Id& id, Row* row) {
+  CHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::DB));
+  if (CantAccessDatabase())
+    return;
+
+  sql::Statement statement(DB()->GetCachedStatement(SQL_FROM_HERE,
+      base::StringPrintf("SELECT * FROM %s WHERE id=?",
+                         kAutocompletePredictorTableName).c_str()));
+  statement.BindString(0, id);
+
+  bool success = StepAndInitializeRow(&statement, row);
+  DCHECK(success) << "Failed to get row " << id << " from "
+                  << kAutocompletePredictorTableName;
+}
+
+void AutocompleteActionPredictorTable::GetAllRows(Rows* row_buffer) {
+  CHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::DB));
+  if (CantAccessDatabase())
+    return;
+
+  row_buffer->clear();
+
+  sql::Statement statement(DB()->GetCachedStatement(SQL_FROM_HERE,
+      base::StringPrintf(
+          "SELECT * FROM %s", kAutocompletePredictorTableName).c_str()));
+
+  Row row;
+  while (StepAndInitializeRow(&statement, &row))
+    row_buffer->push_back(row);
+}
+
+void AutocompleteActionPredictorTable::AddRow(
+    const AutocompleteActionPredictorTable::Row& row) {
+  CHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::DB));
+  if (CantAccessDatabase())
+    return;
+
+  AddAndUpdateRows(Rows(1, row), Rows());
+}
+
+void AutocompleteActionPredictorTable::UpdateRow(
+    const AutocompleteActionPredictorTable::Row& row) {
+  CHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::DB));
+  if (CantAccessDatabase())
+    return;
+
+  AddAndUpdateRows(Rows(), Rows(1, row));
+}
+
+void AutocompleteActionPredictorTable::AddAndUpdateRows(
+    const Rows& rows_to_add,
+    const Rows& rows_to_update) {
+  CHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::DB));
+  if (CantAccessDatabase())
+    return;
+
+  if (!DB()->BeginTransaction())
+    return;
+  for (Rows::const_iterator it = rows_to_add.begin();
+       it != rows_to_add.end(); ++it) {
+    sql::Statement statement(DB()->GetCachedStatement(SQL_FROM_HERE,
+        base::StringPrintf(
+            "INSERT INTO %s "
+            "(id, user_text, url, number_of_hits, number_of_misses) "
+            "VALUES (?,?,?,?,?)", kAutocompletePredictorTableName).c_str()));
+    BindRowToStatement(*it, &statement);
+    if (!statement.Run()) {
+      DB()->RollbackTransaction();
+      return;
+    }
+  }
+  for (Rows::const_iterator it = rows_to_update.begin();
+       it != rows_to_update.end(); ++it) {
+    sql::Statement statement(DB()->GetCachedStatement(SQL_FROM_HERE,
+        base::StringPrintf(
+            "UPDATE %s "
+            "SET id=?, user_text=?, url=?, number_of_hits=?, number_of_misses=?"
+            " WHERE id=?1", kAutocompletePredictorTableName).c_str()));
+    BindRowToStatement(*it, &statement);
+    if (!statement.Run()) {
+      DB()->RollbackTransaction();
+      return;
+    }
+    DCHECK_GT(DB()->GetLastChangeCount(), 0);
+  }
+  DB()->CommitTransaction();
+}
+
+void AutocompleteActionPredictorTable::DeleteRows(
+    const std::vector<Row::Id>& id_list) {
+  CHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::DB));
+  if (CantAccessDatabase())
+    return;
+
+  sql::Statement statement(DB()->GetUniqueStatement(base::StringPrintf(
+      "DELETE FROM %s WHERE id=?",
+      kAutocompletePredictorTableName).c_str()));
+
+  if (!DB()->BeginTransaction())
+    return;
+  for (std::vector<Row::Id>::const_iterator it = id_list.begin();
+       it != id_list.end(); ++it) {
+    statement.BindString(0, *it);
+    if (!statement.Run()) {
+      DB()->RollbackTransaction();
+      return;
+    }
+    statement.Reset(true);
+  }
+  DB()->CommitTransaction();
+}
+
+void AutocompleteActionPredictorTable::DeleteAllRows() {
+  CHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::DB));
+  if (CantAccessDatabase())
+    return;
+
+  sql::Statement statement(DB()->GetCachedStatement(SQL_FROM_HERE,
+      base::StringPrintf("DELETE FROM %s",
+                         kAutocompletePredictorTableName).c_str()));
+
+  statement.Run();
+}
+
+AutocompleteActionPredictorTable::AutocompleteActionPredictorTable()
+    : PredictorTableBase() {
+}
+
+AutocompleteActionPredictorTable::~AutocompleteActionPredictorTable() {
+}
+
+void AutocompleteActionPredictorTable::CreateTableIfNonExistent() {
+  CHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::DB));
+  if (CantAccessDatabase())
+    return;
+
+  if (DB()->DoesTableExist(kAutocompletePredictorTableName))
+    return;
+
+  bool success = DB()->Execute(base::StringPrintf(
+      "CREATE TABLE %s ( "
+      "id TEXT PRIMARY KEY, "
+      "user_text TEXT, "
+      "url TEXT, "
+      "number_of_hits INTEGER, "
+      "number_of_misses INTEGER)", kAutocompletePredictorTableName).c_str());
+  if (!success)
+    ResetDB();
+}
+
+void AutocompleteActionPredictorTable::LogDatabaseStats()  {
+  CHECK(content::BrowserThread::CurrentlyOn(content::BrowserThread::DB));
+  if (CantAccessDatabase())
+    return;
+
+  sql::Statement count_statement(DB()->GetUniqueStatement(
+      base::StringPrintf("SELECT count(id) FROM %s",
+                         kAutocompletePredictorTableName).c_str()));
+  if (!count_statement.Step())
+    return;
+  UMA_HISTOGRAM_COUNTS("AutocompleteActionPredictor.DatabaseRowCount",
+                       count_statement.ColumnInt(0));
+}
+
+}  // namespace predictors