1 /* 2 * Copyright (C) 2010 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.app.backup; 18 19 import android.app.backup.RestoreObserver; 20 import android.app.backup.RestoreSet; 21 import android.app.backup.IRestoreObserver; 22 import android.app.backup.IRestoreSession; 23 import android.content.Context; 24 import android.os.Handler; 25 import android.os.Message; 26 import android.os.RemoteException; 27 import android.util.Log; 28 29 /** 30 * Interface for managing a restore session. 31 * @hide 32 */ 33 public class RestoreSession { 34 static final String TAG = "RestoreSession"; 35 36 final Context mContext; 37 IRestoreSession mBinder; 38 RestoreObserverWrapper mObserver = null; 39 40 /** 41 * Ask the current transport what the available restore sets are. 42 * 43 * @param observer a RestoreObserver object whose restoreSetsAvailable() method will 44 * be called on the application's main thread in order to supply the results of 45 * the restore set lookup by the backup transport. This parameter must not be 46 * null. 47 * @return Zero on success, nonzero on error. The observer's restoreSetsAvailable() 48 * method will only be called if this method returned zero. 49 */ 50 public int getAvailableRestoreSets(RestoreObserver observer) { 51 int err = -1; 52 RestoreObserverWrapper obsWrapper = new RestoreObserverWrapper(mContext, observer); 53 try { 54 err = mBinder.getAvailableRestoreSets(obsWrapper); 55 } catch (RemoteException e) { 56 Log.d(TAG, "Can't contact server to get available sets"); 57 } 58 return err; 59 } 60 61 /** 62 * Restore the given set onto the device, replacing the current data of any app 63 * contained in the restore set with the data previously backed up. 64 * 65 * <p>Callers must hold the android.permission.BACKUP permission to use this method. 66 * 67 * @return Zero on success; nonzero on error. The observer will only receive 68 * progress callbacks if this method returned zero. 69 * @param token The token from {@link #getAvailableRestoreSets()} corresponding to 70 * the restore set that should be used. 71 * @param observer If non-null, this binder points to an object that will receive 72 * progress callbacks during the restore operation. 73 */ 74 public int restoreAll(long token, RestoreObserver observer) { 75 int err = -1; 76 if (mObserver != null) { 77 Log.d(TAG, "restoreAll() called during active restore"); 78 return -1; 79 } 80 mObserver = new RestoreObserverWrapper(mContext, observer); 81 try { 82 err = mBinder.restoreAll(token, mObserver); 83 } catch (RemoteException e) { 84 Log.d(TAG, "Can't contact server to restore"); 85 } 86 return err; 87 } 88 89 /** 90 * Restore a single application from backup. The data will be restored from the 91 * current backup dataset if the given package has stored data there, or from 92 * the dataset used during the last full device setup operation if the current 93 * backup dataset has no matching data. If no backup data exists for this package 94 * in either source, a nonzero value will be returned. 95 * 96 * @return Zero on success; nonzero on error. The observer will only receive 97 * progress callbacks if this method returned zero. 98 * @param packageName The name of the package whose data to restore. If this is 99 * not the name of the caller's own package, then the android.permission.BACKUP 100 * permission must be held. 101 * @param observer If non-null, this binder points to an object that will receive 102 * progress callbacks during the restore operation. 103 */ 104 public int restorePackage(String packageName, RestoreObserver observer) { 105 int err = -1; 106 if (mObserver != null) { 107 Log.d(TAG, "restorePackage() called during active restore"); 108 return -1; 109 } 110 mObserver = new RestoreObserverWrapper(mContext, observer); 111 try { 112 err = mBinder.restorePackage(packageName, mObserver); 113 } catch (RemoteException e) { 114 Log.d(TAG, "Can't contact server to restore package"); 115 } 116 return err; 117 } 118 119 /** 120 * End this restore session. After this method is called, the RestoreSession 121 * object is no longer valid. 122 * 123 * <p><b>Note:</b> The caller <i>must</i> invoke this method to end the restore session, 124 * even if {@link #restorePackage(String, RestoreObserver)} failed. 125 */ 126 public void endRestoreSession() { 127 try { 128 mBinder.endRestoreSession(); 129 } catch (RemoteException e) { 130 Log.d(TAG, "Can't contact server to get available sets"); 131 } finally { 132 mBinder = null; 133 } 134 } 135 136 /* 137 * Nonpublic implementation here 138 */ 139 140 RestoreSession(Context context, IRestoreSession binder) { 141 mContext = context; 142 mBinder = binder; 143 } 144 145 /* 146 * We wrap incoming binder calls with a private class implementation that 147 * redirects them into main-thread actions. This serializes the restore 148 * progress callbacks nicely within the usual main-thread lifecycle pattern. 149 */ 150 private class RestoreObserverWrapper extends IRestoreObserver.Stub { 151 final Handler mHandler; 152 final RestoreObserver mAppObserver; 153 154 static final int MSG_RESTORE_STARTING = 1; 155 static final int MSG_UPDATE = 2; 156 static final int MSG_RESTORE_FINISHED = 3; 157 static final int MSG_RESTORE_SETS_AVAILABLE = 4; 158 159 RestoreObserverWrapper(Context context, RestoreObserver appObserver) { 160 mHandler = new Handler(context.getMainLooper()) { 161 @Override 162 public void handleMessage(Message msg) { 163 switch (msg.what) { 164 case MSG_RESTORE_STARTING: 165 mAppObserver.restoreStarting(msg.arg1); 166 break; 167 case MSG_UPDATE: 168 mAppObserver.onUpdate(msg.arg1, (String)msg.obj); 169 break; 170 case MSG_RESTORE_FINISHED: 171 mAppObserver.restoreFinished(msg.arg1); 172 break; 173 case MSG_RESTORE_SETS_AVAILABLE: 174 mAppObserver.restoreSetsAvailable((RestoreSet[])msg.obj); 175 break; 176 } 177 } 178 }; 179 mAppObserver = appObserver; 180 } 181 182 // Binder calls into this object just enqueue on the main-thread handler 183 public void restoreSetsAvailable(RestoreSet[] result) { 184 mHandler.sendMessage( 185 mHandler.obtainMessage(MSG_RESTORE_SETS_AVAILABLE, result)); 186 } 187 188 public void restoreStarting(int numPackages) { 189 mHandler.sendMessage( 190 mHandler.obtainMessage(MSG_RESTORE_STARTING, numPackages, 0)); 191 } 192 193 public void onUpdate(int nowBeingRestored, String currentPackage) { 194 mHandler.sendMessage( 195 mHandler.obtainMessage(MSG_UPDATE, nowBeingRestored, 0, currentPackage)); 196 } 197 198 public void restoreFinished(int error) { 199 mHandler.sendMessage( 200 mHandler.obtainMessage(MSG_RESTORE_FINISHED, error, 0)); 201 } 202 } 203 } 204
