Added in API level 21

Summary: Methods | Inherited Methods

PackageInstaller.Session

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Kotlin |Java

public static class PackageInstaller.Session
extends Object implements Closeable

java.lang.Object
↳	android.content.pm.PackageInstaller.Session

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An installation that is being actively staged. For an install to succeed, all existing and new packages must have identical package names, version codes, and signing certificates.

A session may contain any number of split packages. If the application does not yet exist, this session must include a base package.

If an APK included in this session is already defined by the existing installation (for example, the same split name), the APK in this session will replace the existing APK.

In such a case that multiple packages need to be committed simultaneously, multiple sessions can be referenced by a single multi-package session. This session is created with no package name and calling SessionParams.setMultiPackage(). The individual session IDs can be added with addChildSessionId(int) and commit of the multi-package session will result in all child sessions being committed atomically.

Summary

Public methods
void	abandon() Completely abandon this session, destroying all staged data and rendering it invalid.
void	addChildSessionId(int sessionId) Adds a session ID to the set of sessions that will be committed atomically when this session is committed.
void	close() Release this session object.
void	commit(IntentSender statusReceiver) Attempt to commit everything staged in this session.
void	fsync(OutputStream out) Ensure that any outstanding data for given stream has been committed to disk.
PersistableBundle	getAppMetadata()
int[]	getChildSessionIds()
String[]	getNames() Return all APK names contained in this session.
int	getParentSessionId()
boolean	isApplicationEnabledSettingPersistent()
boolean	isMultiPackage()
boolean	isRequestUpdateOwnership()
boolean	isStaged()
InputStream	openRead(String name) Open a stream to read an APK file from the session.
OutputStream	openWrite(String name, long offsetBytes, long lengthBytes) Open a stream to write an APK file into the session.
void	removeChildSessionId(int sessionId) Removes a session ID from the set of sessions that will be committed atomically when this session is committed.
void	removeSplit(String splitName) Removes a split.
void	requestChecksums(String name, int required, List<Certificate> trustedInstallers, Executor executor, PackageManager.OnChecksumsReadyListener onChecksumsReadyListener) Requests checksums for the APK file in session.
void	requestUserPreapproval(PackageInstaller.PreapprovalDetails details, IntentSender statusReceiver) Attempt to request the approval before committing this session.
void	setAppMetadata(PersistableBundle data) Optionally set the app metadata.
void	setChecksums(String name, List<Checksum> checksums, byte[] signature) This method was deprecated in API level 31. do not use installer-provided checksums, use platform-enforced checksums e.g. Checksum.TYPE_WHOLE_MERKLE_ROOT_4K_SHA256 in PackageManager.requestChecksums.
void	setStagingProgress(float progress) Set current progress of staging this session.
void	transfer(String packageName) Transfer the session to a new owner.

Inherited methods
From class java.lang.Object Object clone() Creates and returns a copy of this object. boolean equals(Object obj) Indicates whether some other object is "equal to" this one. void finalize() Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. final Class<?> getClass() Returns the runtime class of this Object. int hashCode() Returns a hash code value for the object. final void notify() Wakes up a single thread that is waiting on this object's monitor. final void notifyAll() Wakes up all threads that are waiting on this object's monitor. String toString() Returns a string representation of the object. final void wait(long timeoutMillis, int nanos) Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed. final void wait(long timeoutMillis) Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed. final void wait() Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
From interface java.io.Closeable abstract void close() Closes this stream and releases any system resources associated with it.
From interface java.lang.AutoCloseable abstract void close() Closes this resource, relinquishing any underlying resources.

Public methods

abandon

Added in API level 21

public void abandon ()

Completely abandon this session, destroying all staged data and rendering it invalid. Abandoned sessions will be reported to SessionCallback listeners as failures. This is equivalent to PackageInstaller.abandonSession(int).

If the parent is abandoned, all children will also be abandoned. Any written data would be destroyed and the created Session information will be discarded.

addChildSessionId

Added in API level 29

public void addChildSessionId (int sessionId)

Adds a session ID to the set of sessions that will be committed atomically when this session is committed.

If the parent is staged or has rollback enabled, all children must have the same properties.

If the parent is abandoned, all children will also be abandoned.

Parameters
sessionId	int: the session ID to add to this multi-package session.

close

Added in API level 21

public void close ()

Release this session object. You can open the session again if it hasn't been finalized.

commit

Added in API level 21

public void commit (IntentSender statusReceiver)

Attempt to commit everything staged in this session. This may require user intervention, and so it may not happen immediately. The final result of the commit will be reported through the given callback.

Once this method is called, the session is sealed and no additional mutations may be performed on the session. In case of device reboot or data loader transient failure before the session has been finalized, you may commit the session again.

If the installer is the device owner, the affiliated profile owner, or has received user pre-approval of this session, there will be no user intervention.

Parameters
statusReceiver	IntentSender: Called when the state of the session changes. Intents sent to this receiver contain PackageInstaller.EXTRA_STATUS. Refer to the individual status codes on how to handle them. This value cannot be null.

Throws
SecurityException	if streams opened through openWrite(java.lang.String, long, long) are still open.
IllegalArgumentException	if the statusReceiver from an immutable PendingIntent when caller has a target SDK of API version 35 or above.

See also:

• DevicePolicyManager
• requestUserPreapproval(PreapprovalDetails, IntentSender)

fsync

Added in API level 21

public void fsync (OutputStream out)

Ensure that any outstanding data for given stream has been committed to disk. This is only valid for streams returned from openWrite(java.lang.String, long, long).

Parameters
out	OutputStream: This value cannot be null.

Throws
IOException

getAppMetadata

Added in API level 34

public PersistableBundle getAppMetadata ()

Returns
PersistableBundle	A PersistableBundle containing the app metadata set with Session.setAppMetadata(PersistableBundle). In the case where this data does not exist, an empty PersistableBundle is returned. This value cannot be null.

getChildSessionIds

Added in API level 29

public int[] getChildSessionIds ()

Returns
int[]	the set of session IDs that will be committed atomically when this session is committed if this is a multi-package session or null if none exist.

getNames

Added in API level 21

public String[] getNames ()

Return all APK names contained in this session.

This returns all names which have been previously written through openWrite(java.lang.String, long, long) as part of this session.

Returns
String[]	This value cannot be null.

Throws
SecurityException	if called after the session has been abandoned.
IOException

getParentSessionId

Added in API level 29

public int getParentSessionId ()

Returns
int	the session ID of the multi-package session that this belongs to or SessionInfo.INVALID_ID if it does not belong to a multi-package session.

isApplicationEnabledSettingPersistent

Added in API level 34

public boolean isApplicationEnabledSettingPersistent ()

Returns
boolean	true if this session will keep the existing application enabled setting after installation.

isMultiPackage

Added in API level 29

public boolean isMultiPackage ()

Returns
boolean	true if this session will commit more than one package when it is committed.

isRequestUpdateOwnership

Added in API level 34

public boolean isRequestUpdateOwnership ()

Returns
boolean	true if the installer requested the update ownership enforcement for the packages in this session.

See also:

• PackageInstaller.SessionParams.setRequestUpdateOwnership(boolean)

isStaged

Added in API level 29

public boolean isStaged ()

Returns
boolean	true if this session will be staged and applied at next reboot.

openRead

Added in API level 21

public InputStream openRead (String name)

Open a stream to read an APK file from the session.

This is only valid for names which have been previously written through openWrite(java.lang.String, long, long) as part of this session. For example, this stream may be used to calculate a MessageDigest of a written APK before committing.

Parameters
name	String: This value cannot be null.

Returns
InputStream	This value cannot be null.

Throws
SecurityException	if called after the session has been committed or abandoned.
IOException

openWrite

Added in API level 21

public OutputStream openWrite (String name, 
                long offsetBytes, 
                long lengthBytes)

Open a stream to write an APK file into the session.

The returned stream will start writing data at the requested offset in the underlying file, which can be used to resume a partially written file. If a valid file length is specified, the system will preallocate the underlying disk space to optimize placement on disk. It's strongly recommended to provide a valid file length when known.

You can write data into the returned stream, optionally call fsync(java.io.OutputStream) as needed to ensure bytes have been persisted to disk, and then close when finished. All streams must be closed before calling commit(android.content.IntentSender).

Parameters
name	String: arbitrary, unique name of your choosing to identify the APK being written. You can open a file again for additional writes (such as after a reboot) by using the same name. This name is only meaningful within the context of a single install session. This value cannot be null.
offsetBytes	long: offset into the file to begin writing at, or 0 to start at the beginning of the file.
lengthBytes	long: total size of the file being written, used to preallocate the underlying disk space, or -1 if unknown. The system may clear various caches as needed to allocate this space.

Returns
OutputStream	This value cannot be null.

Throws
IOException	if trouble opening the file for writing, such as lack of disk space or unavailable media.
SecurityException	if called after the session has been sealed or abandoned

removeChildSessionId

Added in API level 29

public void removeChildSessionId (int sessionId)

Removes a session ID from the set of sessions that will be committed atomically when this session is committed.

Parameters
sessionId	int: the session ID to remove from this multi-package session.

removeSplit

Added in API level 24

public void removeSplit (String splitName)

Removes a split.

Split removals occur prior to adding new APKs. If upgrading a feature split, it is not expected nor desirable to remove the split prior to upgrading.

When split removal is bundled with new APKs, the packageName must be identical.

Parameters
splitName	String: This value cannot be null.

Throws
IOException

requestChecksums

Added in API level 33

public void requestChecksums (String name, 
                int required, 
                List<Certificate> trustedInstallers, 
                Executor executor, 
                PackageManager.OnChecksumsReadyListener onChecksumsReadyListener)

Requests checksums for the APK file in session.

A possible use case is replying to Intent.ACTION_PACKAGE_NEEDS_VERIFICATION broadcast. The checksums will be returned asynchronously via onChecksumsReadyListener.

By default returns all readily available checksums:

• enforced by platform,
• enforced by the installer.

If the caller needs a specific checksum type, they can specify it as required.

Caution: Android can not verify installer-provided checksums. Make sure you specify trusted installers.

Parameters
name	String: previously written as part of this session. openWrite(String, long, long) This value cannot be null.
required	int: to explicitly request the checksum types. Will incur significant CPU/memory/disk usage. Value is either 0 or a combination of Checksum.TYPE_WHOLE_MERKLE_ROOT_4K_SHA256, Checksum.TYPE_WHOLE_MD5, Checksum.TYPE_WHOLE_SHA1, Checksum.TYPE_WHOLE_SHA256, Checksum.TYPE_WHOLE_SHA512, Checksum.TYPE_PARTIAL_MERKLE_ROOT_1M_SHA256, and Checksum.TYPE_PARTIAL_MERKLE_ROOT_1M_SHA512
trustedInstallers	List: for checksums enforced by installer, which installers are to be trusted. PackageManager.TRUST_ALL will return checksums from any installer, PackageManager.TRUST_NONE disables optimized installer-enforced checksums, otherwise the list has to be a non-empty list of certificates. This value cannot be null.
executor	Executor: the Executor on which to invoke the callback This value cannot be null. Callback and listener events are dispatched through this Executor, providing an easy way to control which thread is used. To dispatch events through the main thread of your application, you can use Context.getMainExecutor(). Otherwise, provide an Executor that dispatches to an appropriate thread.
onChecksumsReadyListener	PackageManager.OnChecksumsReadyListener: called once when the results are available. This value cannot be null.

Throws
CertificateEncodingException	if an encoding error occurs for trustedInstallers.
FileNotFoundException	if the file does not exist.
IllegalArgumentException	if the list of trusted installer certificates is empty.

requestUserPreapproval

Added in API level 34

public void requestUserPreapproval (PackageInstaller.PreapprovalDetails details, 
                IntentSender statusReceiver)

Attempt to request the approval before committing this session. For installers that have been granted the REQUEST_INSTALL_PACKAGES permission, they can request the approval from users before Session.commit(IntentSender) is called. This may require user intervention as well. When user intervention is required, installers will receive a PackageInstaller.STATUS_PENDING_USER_ACTION callback, and PackageInstaller.STATUS_SUCCESS otherwise. In case that requesting user pre-approval is not available, installers will receive PackageInstaller.STATUS_FAILURE_BLOCKED instead. Note that if the users decline the request, this session will be abandoned. If user intervention is required but never resolved, or requesting user pre-approval is not available, you may still call Session.commit(IntentSender) as the typical installation.

Parameters
details	PackageInstaller.PreapprovalDetails: the adequate context to this session for requesting the approval from users prior to commit. This value cannot be null.
statusReceiver	IntentSender: called when the state of the session changes. Intents sent to this receiver contain PackageInstaller.EXTRA_STATUS and the PackageInstaller.EXTRA_PRE_APPROVAL would be true. Refer to the individual status codes on how to handle them. This value cannot be null.

Throws
IllegalArgumentException	when PreapprovalDetails is null.
IllegalArgumentException	if IntentSender is null.
IllegalStateException	if called on a multi-package session (no matter the parent session or any of the children sessions).
IllegalStateException	if called again after this method has been called on this session.
SecurityException	when the caller does not own this session.
SecurityException	if called after the session has been committed or abandoned.

setAppMetadata

Added in API level 34

public void setAppMetadata (PersistableBundle data)

Optionally set the app metadata. The size of this data cannot exceed the maximum allowed. Any existing data from the previous install will not be retained even if no data is set for the current install session. Setting data to null or an empty PersistableBundle will remove any metadata that has previously been set in the same session.

Parameters
data	PersistableBundle: a PersistableBundle containing the app metadata. This value may be null.

Throws
IOException	if writing the data fails.

setChecksums

Added in API level 31
Deprecated in API level 31

public void setChecksums (String name, 
                List<Checksum> checksums, 
                byte[] signature)

This method was deprecated in API level 31.
do not use installer-provided checksums, use platform-enforced checksums e.g. Checksum.TYPE_WHOLE_MERKLE_ROOT_4K_SHA256 in PackageManager.requestChecksums.

Sets installer-provided checksums for the APK file in session.

Parameters
name	String: previously written as part of this session. openWrite(String, long, long) This value cannot be null.
checksums	List: installer intends to make available via PackageManager.requestChecksums or requestChecksums(String, int, List, Executor, OnChecksumsReadyListener). This value cannot be null.
signature	byte: DER PKCS#7 detached signature bytes over binary serialized checksums to enable integrity checking for the checksums or null for no integrity checking. PackageManager.requestChecksums will return the certificate used to create signature. Binary format for checksums: DataOutputStream dos; dos.writeInt(checksum.getType()); dos.writeInt(checksum.getValue().length); dos.write(checksum.getValue()); If using openssl cms, make sure to specify -binary -nosmimecap.

Throws
SecurityException	if called after the session has been committed or abandoned.
IllegalStateException	if checksums for this file have already been added.
IOException

See also:

• openssl cms

setStagingProgress

Added in API level 21

public void setStagingProgress (float progress)

Set current progress of staging this session. Valid values are anywhere between 0 and 1.

Note that this progress may not directly correspond to the value reported by SessionCallback.onProgressChanged(int, float), as the system may carve out a portion of the overall progress to represent its own internal installation work.

Parameters
progress	float

transfer

Added in API level 27}

public void transfer (String packageName)

Transfer the session to a new owner.

Only sessions that update the installing app can be transferred.

After the transfer to a package with a different uid all method calls on the session will cause SecurityExceptions.

Once this method is called, the session is sealed and no additional mutations beside committing it may be performed on the session.

Parameters
packageName	String: The package of the new owner. Needs to hold the INSTALL_PACKAGES permission. This value cannot be null.

Throws
PackageManager.NameNotFoundException	if the new owner could not be found.
SecurityException	if called after the session has been committed or abandoned.
IllegalStateException	if streams opened through {@link #openWrite(java.lang.String,long,long) are still open.
IllegalArgumentException	if packageName is invalid.