1page.title=bmgr 2@jd:body 3 4<!-- quickview box content here --> 5 6<div id="qv-wrapper"> 7<div id="qv"> 8 <h2>bmgr quickview</h2> 9<p><code>bmgr</code> lets you control the backup/restore system on an Android device. 10 11 <h2>In this document</h2> 12 <ol> 13<li><a href="#backup">Forcing a Backup Operation</a></li> 14<li><a href="#restore">Forcing a Restore Operation</a></li> 15<li><a href="#other">Other Commands</a></li> 16 </ol> 17 18 <h2>See also</h2> 19 <ol> 20 <li><a href="{@docRoot}guide/topics/data/backup.html">Data Backup</a></li> 21 </ol> 22 23</div> 24</div> 25 26<!-- normal page content here --> 27 28<p><code>bmgr</code> is a shell tool you can use to interact with the Backup Manager 29on Android devices supporting API Level 8 or greater. It provides commands to induce backup 30and restore operations so that you don't need to repeatedly wipe data or take similar 31intrusive steps in order to test your application's backup agent. These commands are 32accessed via the <a href="{@docRoot}guide/developing/tools/adb.html">adb</a> shell. 33 34<p>For information about adding support for backup in your application, read <a 35href="{@docRoot}guide/topics/data/backup.html">Data Backup</a>, which includes a guide to testing 36your application using {@code bmgr}.</p> 37 38 39<h2 id="backup">Forcing a Backup Operation</h2> 40 41<p>Normally, your application must notify the Backup Manager when its data has changed, via {@link 42android.app.backup.BackupManager#dataChanged()}. The Backup Manager will then invoke your 43backup agent's {@link 44android.app.backup.BackupAgent#onBackup(ParcelFileDescriptor,BackupDataOutput,ParcelFileDescriptor) 45onBackup()} implementation at some time in the future. However, instead of calling {@link 46android.app.backup.BackupManager#dataChanged()}, you can invoke a backup request from the command 47line by running the <code>bmgr backup</code> command: 48 49 <pre class="no-pretty-print">adb shell bmgr backup <em><package></em></pre> 50 51<p><code><em><package></em></code> is the formal package name of the application you wish to 52schedule for 53backup. When you execute this backup command, your application's backup agent will be invoked to 54perform a backup operation at some time in the future (via your {@link 55android.app.backup.BackupAgent#onBackup(ParcelFileDescriptor,BackupDataOutput,ParcelFileDescriptor) 56onBackup()} method), though there is no guarantee when it will occur. However, you can force all 57pending backup operations to run immediately by using the <code>bmgr run</code> command: 58 59 <pre class="no-pretty-print">adb shell bmgr run</pre> 60 61<p>This causes a backup pass to execute immediately, invoking the backup agents of all applications 62that had previously called {@link android.app.backup.BackupManager#dataChanged()} since the 63last backup operation, plus any applications which had been manually scheduled for 64backup via <code>bmgr backup</code>. 65 66 67 68<h2 id="restore">Forcing a Restore Operation</h2> 69 70<p>Unlike backup operations, which are batched together and run on an occasional basis, restore 71operations execute immediately. The Backup Manager currently provides two kinds of restore 72operations. The first kind restores an entire device with the data that has been backed up. This 73is typically performed only when a device is first provisioned (to replicate settings and other 74saved state from the user's previous device) and is an operation that only the system can 75perform. The second kind of restore operation restores 76a single application to its "active" data set; that is, the application will abandon its current 77data and revert to the last-known-good data that is held in the current backup image. You can 78invoke this second restore operation with the {@link 79android.app.backup.BackupManager#requestRestore(RestoreObserver) requestRestore()} method. The 80Backup Manager will then invoke your backup agent's {@link 81android.app.backup.BackupAgent#onRestore(BackupDataInput,int,ParcelFileDescriptor) 82onRestore()} implementation. 83 84<p>While testing your application, you can immediately invoke the restore operation (bypassing the 85{@link android.app.backup.BackupManager#requestRestore(RestoreObserver) requestRestore()} method) 86for your application by using the <code>bmgr restore</code> command: 87 88 <pre class="no-pretty-print">adb shell bmgr restore <em><package></em></pre> 89 90<p><code><em><package></em></code> is the formal Java-style package name of the application 91participating in the backup/restore mechanism, which you would like to restore. The Backup 92Manager will immediately instantiate the application's backup agent and invoke it for restore. This 93will happen even if your application is not currently running. 94 95 96 97 98 99<h2 id="other">Other Commands</h2> 100 101<h3>Wiping data</h3> 102 103<p>The data for a single application can be erased from the active data set on demand. This is 104very useful while you're developing a backup agent, in case bugs lead you to write corrupt data 105or saved state information. You can wipe an application's data with the <code>bmgr wipe</code> 106command: 107 108 <pre class="no-pretty-print">adb shell bmgr wipe <em><package></em></pre> 109 110<p><code><em><package></em></code> is the formal package name of the application whose data 111you wish to 112erase. The next backup operation that the application's agent processes will look as 113though the application had never backed anything up before. 114 115 116<h3>Enabling and disabling backup</h3> 117 118<p>You can see whether the Backup Manager is operational at all with the <code>bmgr 119enabled</code> command: 120 121 <pre class="no-pretty-print">adb shell bmgr enabled</pre> 122 123<p>This might be useful if your application's backup agent is never being invoked for backup, to 124verify whether the operating system thinks it should be performing such operations at all.</p> 125 126<p>You can also directly disable or enable the Backup Manager with this command: 127 128 <pre class="no-pretty-print">adb shell bmgr enable <em><boolean></em></pre> 129 130<p><code><em><boolean></em></code> is either <code>true</code> or <code>false</code>. 131This is equivalent to disabling or enabling backup in the device's main Settings UI.</p> 132 133<p class="warning"><strong>Warning!</strong> When backup is disabled, the current backup transport 134will explicitly wipe 135the entire active data set from its backend storage. This is so that when a user says 136they do <em>not</em> want their data backed up, the Backup Manager respects that wish. No further 137data will be saved from the device, and no restore operations will be possible, unless the Backup 138Manager is re-enabled (either through Settings or through the above <code>bmgr</code> command). 139 140 141 142 143<!-- The following is not useful to applications, but may be some useful information some day... 144 145 146<h2 id="transports">Applying a Backup Transport</h2> 147 148<p>A "backup transport" is the code module responsible for moving backup and restore data 149to and from some storage location. A device can have multipe transports installed, though only 150one is active at any given time. Transports are identified by name. You can see what 151transports are available on your device or emulator by running the 152<code>bmgr list transports</code> command: 153 154 <pre class="no-pretty-print">adb shell bmgr list transports</pre> 155 156<p>The output of this command is a list of the transports available on the device. The currently 157active transport is flagged with a <code>*</code> character. Transport names may look like 158component names (for example, <code>android/com.android.internal.backup.LocalTransport</code>), 159but they need not be, and the strings are never used as direct class references. The use of 160a component-like naming scheme is simply for purposes of preventing name collisions. 161 162<p>You can change which transport is currently active from the command line as well: 163 164 <pre class="no-pretty-print">adb shell bmgr transport <em><name></em></pre> 165 166<p><code><em><name></em></code> is one of the names as printed by the <code>bmgr list 167transports</code> 168command. From this point forward, backup and restore operations will be directed through the 169newly-selected transport. Backup state tracking is managed separately for each transport, so 170switching back and forth between them will not corrupt the saved state. 171 172 173 174 175<h2 id="restoresets">Viewing Restore Sets</h2> 176 177<p>All of the application data that a device has written to its backup transport is tracked 178as a group that is collectively called a "restore set," because each data set is 179most often manipulated during a restore operation. When a device is provisioned for the first 180time, a new restore set is established. You can get a listing of all the restore sets available to 181the current transport by running the <code>bmgr list sets</code> command: 182 183 <pre class="no-pretty-print">adb shell bmgr list sets</pre> 184 185<p>The output is a listing of available restore sets, one per line. The first item on each line is 186a token (a hexadecimal value that identifies the restore set to the transport). Following 187the token is a string that briefly identifies the restore set. 188Only the token is used within the backup and restore mechanism. 189 190 191--> 192