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