/* * Copyright (C) 2009 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 android.app.backup; import android.content.Context; import android.os.ParcelFileDescriptor; import android.util.Log; import java.io.File; /** * A helper class which can be used in conjunction with * {@link android.app.backup.BackupAgentHelper} to manage the backup of a set of * files. Whenever backup is performed, all files changed since the last backup * will be saved in their entirety. During the first time the backup happens, * all the files in the list will be backed up. Note that this should only be * used with small configuration files and not with large binary files. *

* Any files not present in the list of files during the restore procedure will * be ignored. If files present in a previous version of an application are * removed in subsequent versions, it is the responsibility of the developer to * design a mechanism to remove those files. Otherwise files no longer needed * will linger and consume space on the device. *

* STOPSHIP: document! [manages backup of a set of files; restore is totally * opaque] */ public class FileBackupHelper extends FileBackupHelperBase implements BackupHelper { private static final String TAG = "FileBackupHelper"; private static final boolean DEBUG = false; Context mContext; File mFilesDir; String[] mFiles; /** * Construct a helper to manage backup/restore of entire files within the * application's data directory hierarchy. * * @param context The backup agent's Context object * @param files A list of the files to be backed up or restored. */ public FileBackupHelper(Context context, String... files) { super(context); mContext = context; mFilesDir = context.getFilesDir(); mFiles = files; } /** * Based on oldState, determine which of the files from the * application's data directory need to be backed up, write them to the data * stream, and fill in newState with the state as it exists * now. When oldState is null, all the files will * be backed up. *

* This should be called from {@link android.app.backup.BackupAgentHelper} * directly. See * {@link android.app.backup.BackupAgent#onBackup(ParcelFileDescriptor, BackupDataOutput, ParcelFileDescriptor)} * for a description of parameter meanings. */ public void performBackup(ParcelFileDescriptor oldState, BackupDataOutput data, ParcelFileDescriptor newState) { // file names String[] files = mFiles; File base = mContext.getFilesDir(); final int N = files.length; String[] fullPaths = new String[N]; for (int i=0; i