1 /* 2 * Copyright 2024 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.backup.app; 18 19 import android.app.backup.BackupAgent; 20 import android.app.backup.BackupDataInput; 21 import android.app.backup.BackupDataOutput; 22 import android.app.backup.FullBackupDataOutput; 23 import android.os.ParcelFileDescriptor; 24 25 import java.io.File; 26 import java.io.FileWriter; 27 import java.io.IOException; 28 29 /** 30 * Full Backup agent that tries to cast its {@link android.app.Application} object during backup. 31 * 32 * <p>This is used to check whether the app is in restricted mode during backup since casting the 33 * application will throw an exception and fail the backup when in restricted mode. 34 */ 35 public class ApplicationCastingFullBackupAgent extends BackupAgent { 36 @Override onBackup(ParcelFileDescriptor oldState, BackupDataOutput data, ParcelFileDescriptor newState)37 public void onBackup(ParcelFileDescriptor oldState, BackupDataOutput data, 38 ParcelFileDescriptor newState) throws IOException { 39 throw new IllegalStateException("unexpected onBackup"); 40 } 41 42 @Override onRestore(BackupDataInput data, int appVersionCode, ParcelFileDescriptor newState)43 public void onRestore(BackupDataInput data, int appVersionCode, ParcelFileDescriptor newState) 44 throws IOException { 45 throw new IllegalStateException("unexpected onRestore"); 46 } 47 48 @Override onFullBackup(FullBackupDataOutput data)49 public void onFullBackup(FullBackupDataOutput data) throws IOException { 50 CustomApplication customApplication = (CustomApplication) getApplicationContext(); 51 52 // Write a file so that the backup doesn't get rejected for being empty. 53 try (FileWriter fileWriter = new FileWriter(new File(getFilesDir(), "testfile"))) { 54 fileWriter.write("meow"); 55 } 56 57 super.onFullBackup(data); 58 } 59 } 60