| /* |
| * Copyright (C) 2011 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.email.provider; |
| |
| import android.content.ContentResolver; |
| import android.content.Context; |
| |
| /** |
| * Helper class to facilitate EmailProvider's account backup/restore facility. |
| * |
| * Account backup/restore was implemented entirely for the purpose of recovering from database |
| * corruption errors that were/are sporadic and of undetermined cause (though the prevailing wisdom |
| * is that this is due to some kind of memory issue). Rather than have the offending database get |
| * deleted by SQLiteDatabase and forcing the user to recreate his accounts from scratch, it was |
| * decided to backup accounts when created/modified and then restore them if 1) there are no |
| * accounts in the database and 2) there are backup accounts. This, at least, would cause user's |
| * email data for IMAP/EAS to be re-synced and prevent the worst outcomes from occurring. |
| * |
| * To accomplish backup/restore, we use the facility now built in to EmailProvider to store a |
| * backup version of the Account and HostAuth tables in a second database (EmailProviderBackup.db) |
| * |
| * TODO: We might look into having our own DatabaseErrorHandler that tries to be clever about |
| * determining whether or not a "corrupt" database is truly corrupt; the problem here is that it |
| * has proven impossible to reproduce the bug, and therefore any "solution" of this kind of utterly |
| * impossible to test in the wild. |
| */ |
| public class AccountBackupRestore { |
| /** |
| * Backup user Account and HostAuth data into our backup database |
| * |
| * TODO Make EmailProvider do this automatically. |
| */ |
| public static void backup(Context context) { |
| ContentResolver resolver = context.getContentResolver(); |
| resolver.update(EmailProvider.ACCOUNT_BACKUP_URI, null, null, null); |
| } |
| } |