<div id="qv-wrapper">
<div id="qv">
<h2>bmgr quickview</h2>
-<p><code>bmgr</code> lets you inspect and control the backup/restore system on an Android device.
+<p><code>bmgr</code> lets you control the backup/restore system on an Android device.
<h2>In this document</h2>
<ol>
-<li><a href="#transports">About backup transports</a></li>
-<li><a href="#restoresets">About restore sets</a></li>
-<li><a href="#backup">Forcing a backup operation</a></li>
-<li><a href="#restore">Forcing a restore operation</a></li>
-<li><a href="#other">Other commands</a></li>
+<li><a href="#backup">Forcing a Backup Operation</a></li>
+<li><a href="#restore">Forcing a Restore Operation</a></li>
+<li><a href="#other">Other Commands</a></li>
</ol>
</div>
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-<p><code>bmgr</code> is a shell tool that developers can use to interact with the Backup Manager
-on Android devices supporting API version 8 or later. It provides commands for inducing backup
-and restore operations on demand so that you do not need to repeatedly wipe data or take similar
-intrusive steps to test the operation of an application's backup agent. These commands are
+<p><code>bmgr</code> is a shell tool you can use to interact with the Backup Manager
+on Android devices supporting API Level 8 or greater. It provides commands to induce backup
+and restore operations so that you don't need to repeatedly wipe data or take similar
+intrusive steps in order to test your application's backup agent. These commands are
accessed via the <a href="{@docRoot}guide/developing/tools/adb.html">adb</a> shell.
-<p>There are a couple of basic concepts used by the Backup Manager that are built into the way
-that <code>bmgr</code> operates. These are <a href="#transports">backup transports</a> and
-<a href="#restoresets">restore sets</a>.
-<a name="transports"></a>
-<h2>About backup transports</h2>
+<h2 id="backup">Forcing a Backup Operation</h2>
-<p>A <em>backup transport</em> is the code module responsible for moving backup and restore data
-to and from some storage location. A device can have multipe transports installed, though only
-one is active at any given time. Transports are identified by name. You can see what
-transports are available on your device or emulator by running the
-<code>bmgr list transports</code> command:
+<p>Normally, your application must notify the Backup Manager when its data has changed, via {@link
+android.app.backup.BackupManager#dataChanged()}. The Backup Manager will then invoke your
+backup agent's {@link
+android.app.backup.BackupAgent#onBackup(ParcelFileDescriptor,BackupDataOutput,ParcelFileDescriptor)
+onBackup()} implementation at some time in the future. However, instead of calling {@link
+android.app.backup.BackupManager#dataChanged()}, you can invoke a backup request from the command
+line by running the <code>bmgr backup</code> command:
- <pre>adb shell bmgr list transports</pre>
+ <pre class="no-pretty-print">adb shell bmgr backup <em><package></em></pre>
-<p>The output of this command is a list of the transports available on the device. The currently
-active transport is flagged with a <code>*</code> character. Transport names may look like
-component names -- for example, <code>android/com.android.internal.backup.LocalTransport</code> --
-but they need not be, and the strings are never used as direct class references. The use of
-a component-like naming scheme is simply for purposes of preventing name collisions.
+<p><code><em><package></em></code> is the formal package name of the application you wish to
+schedule for
+backup. When you execute this backup command, your application's backup agent will be invoked to
+perform a backup operation at some time in the future (via your {@link
+android.app.backup.BackupAgent#onBackup(ParcelFileDescriptor,BackupDataOutput,ParcelFileDescriptor)
+onBackup()} method), though there is no guarantee when it will occur. However, you can force all
+pending backup operations to run immediately by using the <code>bmgr run</code> command:
-<p>You can change which transport is currently active from the command line as well:
+ <pre class="no-pretty-print">adb shell bmgr run</pre>
- <pre>adb shell bmgr transport NAME</pre>
+<p>This causes a backup pass to execute immediately, invoking the backup agents of all applications
+that had previously called {@link android.app.backup.BackupManager#dataChanged()} since the
+last backup operation, plus any applications which had been manually scheduled for
+backup via <code>bmgr backup</code>.
-<p>where <code>NAME</code> is one of the names as printed by the <code>bmgr list transports</code>
-command. From this point forward, backup and restore operations will be directed through the
-newly-selected transport. Backup state tracking is managed separately for each transport, so
-switching back and forth between them will not corrupt the saved state.
-<a name="restoresets"></a>
-<h2>About restore sets</h2>
+<h2 id="restore">Forcing a Restore Operation</h2>
-<p>All of the application data that a device has written to a given backup transport is tracked
-together, and is collectively sometimes called a <em>restore set,</em> because the typical use
-of the data set is during restore operations. Each time a device is initially provisioned, a
-new data set is established. The user can get a listing of all the data sets that can be
-restored through the current transport by running this shell command:
+<p>Unlike backup operations, which are batched together and run on an occasional basis, restore
+operations execute immediately. The Backup Manager currently provides two kinds of restore
+operations. The first kind restores an entire device with the data that has been backed up. This
+is typically performed only when a device is first provisioned (to replicate settings and other
+saved state from the user's previous device) and is an operation that only the system can
+perform. The second kind of restore operation restores
+a single application to its "active" data set; that is, the application will abandon its current
+data and revert to the last-known-good data that is held in the current backup image. You can
+invoke this second restore operation with the {@link
+android.app.backup.BackupManager#requestRestore(RestoreObserver) requestRestore()} method. The
+Backup Manager will then invoke your backup agent's {@link
+android.app.backup.BackupAgent#onRestore(BackupDataInput,int,ParcelFileDescriptor)
+onRestore()} implementation.
- <pre>adb shell bmgr list sets</pre>
+<p>While testing your application, you can immediately invoke the restore operation (bypassing the
+{@link android.app.backup.BackupManager#requestRestore(RestoreObserver) requestRestore()} method)
+for your application by using the <code>bmgr restore</code> command:
-<p>The output is listing of available restore sets, one per line. The first item on each line is
-a <em>token,</em> a number in hexadecimal that identifies the restore set to the transport. After
-that is a string that may provide some brief identifying information about the restore set. Only
-the token is actually used within the backup and restore mechanism.
+ <pre class="no-pretty-print">adb shell bmgr restore <em><package></em></pre>
+<p><code><em><package></em></code> is the formal Java-style package name of the application
+participating in the backup/restore mechanism, which you would like to restore. The Backup
+Manager will immediately instantiate the application's backup agent and invoke it for restore. This
+will happen even if your application is not currently running.
-<a name="backup"></a>
-<h2>Forcing a backup operation</h2>
-<p>Normally, applications notify the backup manager directly that their data has changed, in
-response to which the backup manager will make sure to invoke that application's agent when the
-next backup operation is run. You can simulate this manually from the command line if you wish,
-by running this shell command:
- <pre>adb shell bmgr backup PACKAGE</pre>
-<p><code>PACKAGE</code> is the formal package name of the application you wish to schedule for
-backup. At this point you know that the application's agent will be invoked for backup at some
-point in the future, though there is no hard guarantee of when that will occur. You can force
-all pending backup operations to run immediately by using the following command:
- <pre>adb shell bmgr run</pre>
+<h2 id="other">Other Commands</h2>
-<p>This causes a backup pass to execute immediately, invoking the agents of all applications that
-had called <code>BackupManager.dataChanged()</code> since the time of the last backup operation,
-plus any applications which had been manually scheduled for backup via
-<code>bmgr backup PACKAGE</code>.
+<p>The data for a single application can be erased from the active data set on demand. This is
+very useful while you're developing a backup agent, in case bugs lead you to write corrupt data
+or saved state information. You can wipe an application's data with the <code>bmgr wipe</code>
+command:
+ <pre class="no-pretty-print">adb shell bmgr wipe <em><package></em></pre>
-<a name="restore"></a>
-<h2>Forcing a restore operation</h2>
+<p><code><em><package></em></code> is the formal package name of the application whose data
+you wish to
+erase. The next backup operation that the application's agent processes will look as
+though the application had never backed anything up before.
-<p>Unlike backup operations, which are batched together and run on an occasional basis, restore
-operations execute immediately. The backup manager currently provides two kinds of restore
-operations. The first restores an entire device with the data from a given restore set. This
-is typically only performed when a device is first provisioned, to replicate settings and other
-such saved state from the user's previous device. The second kind of restore operation restores
-a single application from the <em>active</em> data set; that is, from the data set currently
-being written to by backup operations. This second form is available as part of the public API.
-It allows applications to abandon their current data and revert to the last-known-good data as
-represented in their current backup image.
+<p>You can see whether the Backup Manager is operational at all with the <code>bmgr
+enabled</code> command:
-<p>A full-system restore operation can be initiated with this shell command:
+ <pre class="no-pretty-print">adb shell bmgr enabled</pre>
- <pre>adb shell bmgr restore TOKEN</pre>
+<p>This might be useful if your application's backup agent is never being invoked for backup, to
+verify whether the operating system thinks it should be performing such operations at all.</p>
-<p>where <code>TOKEN</code> is the desired restore set's token as printed out by the <code>bmgr
-list sets</code> command. <strong>Warning!</strong> This operation will <em>replace</em> the
-data of all backup-enabled applications with the contents of the given restore set. Be careful,
-and be aware of the potential consequences.
+<p>You can also directly disable or enable the Backup Manager with this command:
-<p>A single-application restore operation does not reference a restore set token; it always uses
-the data from the currently active data set. You can induce such an operation from the command
-line like this:
+ <pre class="no-pretty-print">adb shell bmgr enable <em><boolean></em></pre>
- <pre>adb shell bmgr restore PACKAGE</pre>
+<p><code><em><boolean></em></code> is either <code>true</code> or <code>false</code>.
+This is equivalent to disabling or enabling backup in the device's main Settings UI.</p>
-<p><code>PACKAGE</code> is the formal package name of an application that is participating in the
-backup/restore mechanism. The backup manager will immediately instantiate the application's
-agent and invoke it for restore.
+<p class="warning"><strong>Warning!</strong> When backup is disabled, the current backup transport
+will explicitly wipe
+the entire active data set from its backend storage. This is so that when a user says
+they do <em>not</em> want their data backed up, the Backup Manager respects that wish. No further
+data will be saved from the device, and no restore operations will be possible, unless the Backup
+Manager is re-enabled (either through Settings or through the above <code>bmgr</code> command).
-<a name="other"></a>
-<h2>Other commands</h2>
-<p>The data for a single application can be erased from the active data set on demand. This is
-very useful during development of backup agents, in case bugs lead you to write corrupt data
-or saved state information. The shell command for wiping an application's data is this:
- <pre>adb shell bmgr wipe PACKAGE</pre>
-<p><code>PACKAGE</code> is the formal package name of the application whose data you wish to
-erase. The next backup operation that the application's agent processes will look as
-though the application had never backed anything up before.
+<!-- The following is not useful to applications, but may be some useful information some day...
+
+
+<h2 id="transports">Applying a Backup Transport</h2>
+
+<p>A "backup transport" is the code module responsible for moving backup and restore data
+to and from some storage location. A device can have multipe transports installed, though only
+one is active at any given time. Transports are identified by name. You can see what
+transports are available on your device or emulator by running the
+<code>bmgr list transports</code> command:
+
+ <pre class="no-pretty-print">adb shell bmgr list transports</pre>
+
+<p>The output of this command is a list of the transports available on the device. The currently
+active transport is flagged with a <code>*</code> character. Transport names may look like
+component names (for example, <code>android/com.android.internal.backup.LocalTransport</code>),
+but they need not be, and the strings are never used as direct class references. The use of
+a component-like naming scheme is simply for purposes of preventing name collisions.
+
+<p>You can change which transport is currently active from the command line as well:
+
+ <pre class="no-pretty-print">adb shell bmgr transport <em><name></em></pre>
+
+<p><code><em><name></em></code> is one of the names as printed by the <code>bmgr list
+transports</code>
+command. From this point forward, backup and restore operations will be directed through the
+newly-selected transport. Backup state tracking is managed separately for each transport, so
+switching back and forth between them will not corrupt the saved state.
+
+
+
-<p>You can see whether the backup manager is operational at all by running this command:
+<h2 id="restoresets">Viewing Restore Sets</h2>
- <pre>adb shell bmgr enabled</pre>
+<p>All of the application data that a device has written to its backup transport is tracked
+as a group that is collectively called a "restore set," because each data set is
+most often manipulated during a restore operation. When a device is provisioned for the first
+time, a new restore set is established. You can get a listing of all the restore sets available to
+the current transport by running the <code>bmgr list sets</code> command:
-<p>This might be useful if your application's agent is never being invoked for backup, to verify
-whether the operating system thinks it should be performing such operations at all. You can also
-directly disable or enable the backup manager with this command:
+ <pre class="no-pretty-print">adb shell bmgr list sets</pre>
- <pre>adb shell bmgr enable BOOLEAN</pre>
+<p>The output is a listing of available restore sets, one per line. The first item on each line is
+a token (a hexadecimal value that identifies the restore set to the transport). Following
+the token is a string that briefly identifies the restore set.
+Only the token is used within the backup and restore mechanism.
-<p>where <code>BOOLEAN</code> is either <code>true</code> or <code>false</code>. This is
-equivalent to disabling or enabling backup in the device's main Settings UI.
-<strong>Warning!</strong> When backup is disabled, the current transport will explicitly wipe
-the entire active data set from its backend storage. This is so that when a user says that no,
-they do not want their data backed up, the backup manager respects that wish. No further data
-will be saved from the device, and no restore operations will be possible, unless the backup
-manager is re-enabled (either through Settings or through the above <code>bmgr</code> command).
+-->