JobScheduler
public
abstract
class
JobScheduler
extends Object
java.lang.Object | |
↳ | android.app.job.JobScheduler |
This is an API for scheduling various types of jobs against the framework that will be executed in your application's own process.
See JobInfo
for more description of the types of jobs that can be run
and how to construct them. You will construct these JobInfo objects and pass them to the
JobScheduler with schedule(android.app.job.JobInfo)
. When the criteria declared are met, the
system will execute this job on your application's JobService
.
You identify the service component that implements the logic for your job when you
construct the JobInfo using
JobInfo.Builder.Builder(int, android.content.ComponentName)
.
The framework will be intelligent about when it executes jobs, and attempt to batch and defer them as much as possible. Typically, if you don't specify a deadline on a job, it can be run at any moment depending on the current state of the JobScheduler's internal queue.
Starting in Android version Build.VERSION_CODES.UPSIDE_DOWN_CAKE
,
JobScheduler may try to optimize job execution by shifting execution to times with more available
system resources in order to lower user impact. Factors in system health include sufficient
battery, idle, charging, and access to an un-metered network. Jobs will initially be treated as
if they have all these requirements, but as their deadlines approach, restrictions will become
less strict. Requested requirements will not be affected by this change.
While a job is running, the system holds a wakelock on behalf of your app. For this reason, you do not need to take any action to guarantee that the device stays awake for the duration of the job.
You do not
instantiate this class directly; instead, retrieve it through
Context.getSystemService(Context.JOB_SCHEDULER_SERVICE)
.
Prior to Android version Build.VERSION_CODES.S
, jobs could only have
a maximum of 100 jobs scheduled at a time. Starting with Android version
Build.VERSION_CODES.S
, that limit has been increased to 150.
Expedited jobs also count towards the limit.
In Android version Build.VERSION_CODES.LOLLIPOP
, jobs had a maximum
execution time of one minute. Starting with Android version
Build.VERSION_CODES.M
and ending with Android version
Build.VERSION_CODES.R
, jobs had a maximum execution time of 10 minutes.
Starting from Android version Build.VERSION_CODES.S
, jobs will still be
stopped after 10 minutes if the system is busy or needs the resources, but if not, jobs
may continue running longer than 10 minutes.
Note: Beginning with API 30
(Build.VERSION_CODES.R
), JobScheduler will throttle runaway applications.
Calling schedule(android.app.job.JobInfo)
and other such methods with very high frequency can have a
high cost and so, to make sure the system doesn't get overwhelmed, JobScheduler will begin
to throttle apps, regardless of target SDK version.
See also:
Summary
Constants | |
---|---|
int |
PENDING_JOB_REASON_APP
The app is in a state that prevents the job from running (eg. |
int |
PENDING_JOB_REASON_APP_STANDBY
The current standby bucket prevents the job from running. |
int |
PENDING_JOB_REASON_BACKGROUND_RESTRICTION
The app is restricted from running in the background. |
int |
PENDING_JOB_REASON_CONSTRAINT_BATTERY_NOT_LOW
The requested battery-not-low constraint is not satisfied. |
int |
PENDING_JOB_REASON_CONSTRAINT_CHARGING
The requested charging constraint is not satisfied. |
int |
PENDING_JOB_REASON_CONSTRAINT_CONNECTIVITY
The requested connectivity constraint is not satisfied. |
int |
PENDING_JOB_REASON_CONSTRAINT_CONTENT_TRIGGER
The requested content trigger constraint is not satisfied. |
int |
PENDING_JOB_REASON_CONSTRAINT_DEADLINE
The override deadline has not transpired. |
int |
PENDING_JOB_REASON_CONSTRAINT_DEVICE_IDLE
The requested idle constraint is not satisfied. |
int |
PENDING_JOB_REASON_CONSTRAINT_MINIMUM_LATENCY
The minimum latency has not transpired. |
int |
PENDING_JOB_REASON_CONSTRAINT_PREFETCH
The system's estimate of when the app will be launched is far away enough to warrant delaying this job. |
int |
PENDING_JOB_REASON_CONSTRAINT_STORAGE_NOT_LOW
The requested storage-not-low constraint is not satisfied. |
int |
PENDING_JOB_REASON_DEVICE_STATE
The job is being deferred due to the device state (eg. |
int |
PENDING_JOB_REASON_EXECUTING
The job is currently running and is therefore not pending. |
int |
PENDING_JOB_REASON_INVALID_JOB_ID
The job doesn't exist. |
int |
PENDING_JOB_REASON_JOB_SCHEDULER_OPTIMIZATION
JobScheduler thinks it can defer this job to a more optimal running time. |
int |
PENDING_JOB_REASON_QUOTA
The app has consumed all of its current quota. |
int |
PENDING_JOB_REASON_UNDEFINED
There is no known reason why the job is pending. |
int |
PENDING_JOB_REASON_USER
JobScheduler is respecting one of the user's actions (eg. |
int |
RESULT_FAILURE
Returned from |
int |
RESULT_SUCCESS
Returned from |
Public constructors | |
---|---|
JobScheduler()
|
Public methods | |
---|---|
boolean
|
canRunUserInitiatedJobs()
Returns |
abstract
void
|
cancel(int jobId)
Cancel the specified job. |
abstract
void
|
cancelAll()
Cancel all jobs that have been scheduled in the current namespace by the calling application. |
void
|
cancelInAllNamespaces()
Cancel all jobs that have been scheduled by the calling application, regardless of namespace. |
abstract
int
|
enqueue(JobInfo job, JobWorkItem work)
Similar to |
JobScheduler
|
forNamespace(String namespace)
Get a JobScheduler instance that is dedicated to a specific namespace. |
abstract
List<JobInfo>
|
getAllPendingJobs()
Retrieve all jobs that have been scheduled by the calling application. |
String
|
getNamespace()
Get the namespace this JobScheduler instance is operating in. |
abstract
JobInfo
|
getPendingJob(int jobId)
Look up the description of a scheduled job. |
int
|
getPendingJobReason(int jobId)
Returns a reason why the job is pending and not currently executing. |
int[]
|
getPendingJobReasons(int jobId)
Returns potential reasons why the job with the given |
List<PendingJobReasonsInfo>
|
getPendingJobReasonsHistory(int jobId)
For the given |
Map<String, List<JobInfo>>
|
getPendingJobsInAllNamespaces()
Retrieve all jobs that have been scheduled by the calling application within the current namespace. |
abstract
int
|
schedule(JobInfo job)
Schedule a job to be executed. |
Inherited methods | |
---|---|
Constants
PENDING_JOB_REASON_APP
public static final int PENDING_JOB_REASON_APP
The app is in a state that prevents the job from running
(eg. the JobService
component is disabled).
Constant Value: 1 (0x00000001)
PENDING_JOB_REASON_APP_STANDBY
public static final int PENDING_JOB_REASON_APP_STANDBY
The current standby bucket prevents the job from running.
Constant Value: 2 (0x00000002)
PENDING_JOB_REASON_BACKGROUND_RESTRICTION
public static final int PENDING_JOB_REASON_BACKGROUND_RESTRICTION
The app is restricted from running in the background.
Constant Value: 3 (0x00000003)
PENDING_JOB_REASON_CONSTRAINT_BATTERY_NOT_LOW
public static final int PENDING_JOB_REASON_CONSTRAINT_BATTERY_NOT_LOW
The requested battery-not-low constraint is not satisfied.
Constant Value: 4 (0x00000004)
PENDING_JOB_REASON_CONSTRAINT_CHARGING
public static final int PENDING_JOB_REASON_CONSTRAINT_CHARGING
The requested charging constraint is not satisfied.
Constant Value: 5 (0x00000005)
PENDING_JOB_REASON_CONSTRAINT_CONNECTIVITY
public static final int PENDING_JOB_REASON_CONSTRAINT_CONNECTIVITY
The requested connectivity constraint is not satisfied.
See also:
Constant Value: 6 (0x00000006)
PENDING_JOB_REASON_CONSTRAINT_CONTENT_TRIGGER
public static final int PENDING_JOB_REASON_CONSTRAINT_CONTENT_TRIGGER
The requested content trigger constraint is not satisfied.
Constant Value: 7 (0x00000007)
PENDING_JOB_REASON_CONSTRAINT_DEADLINE
public static final int PENDING_JOB_REASON_CONSTRAINT_DEADLINE
The override deadline has not transpired.
Constant Value: 16 (0x00000010)
PENDING_JOB_REASON_CONSTRAINT_DEVICE_IDLE
public static final int PENDING_JOB_REASON_CONSTRAINT_DEVICE_IDLE
The requested idle constraint is not satisfied.
Constant Value: 8 (0x00000008)
PENDING_JOB_REASON_CONSTRAINT_MINIMUM_LATENCY
public static final int PENDING_JOB_REASON_CONSTRAINT_MINIMUM_LATENCY
The minimum latency has not transpired.
See also:
Constant Value: 9 (0x00000009)
PENDING_JOB_REASON_CONSTRAINT_PREFETCH
public static final int PENDING_JOB_REASON_CONSTRAINT_PREFETCH
The system's estimate of when the app will be launched is far away enough to warrant delaying this job.
Constant Value: 10 (0x0000000a)
PENDING_JOB_REASON_CONSTRAINT_STORAGE_NOT_LOW
public static final int PENDING_JOB_REASON_CONSTRAINT_STORAGE_NOT_LOW
The requested storage-not-low constraint is not satisfied.
Constant Value: 11 (0x0000000b)
PENDING_JOB_REASON_DEVICE_STATE
public static final int PENDING_JOB_REASON_DEVICE_STATE
The job is being deferred due to the device state (eg. Doze, battery saver, memory usage, thermal status, etc.).
Constant Value: 12 (0x0000000c)
PENDING_JOB_REASON_EXECUTING
public static final int PENDING_JOB_REASON_EXECUTING
The job is currently running and is therefore not pending.
Constant Value: -1 (0xffffffff)
PENDING_JOB_REASON_INVALID_JOB_ID
public static final int PENDING_JOB_REASON_INVALID_JOB_ID
The job doesn't exist.
Constant Value: -2 (0xfffffffe)
PENDING_JOB_REASON_JOB_SCHEDULER_OPTIMIZATION
public static final int PENDING_JOB_REASON_JOB_SCHEDULER_OPTIMIZATION
JobScheduler thinks it can defer this job to a more optimal running time.
Constant Value: 13 (0x0000000d)
PENDING_JOB_REASON_QUOTA
public static final int PENDING_JOB_REASON_QUOTA
The app has consumed all of its current quota.
Constant Value: 14 (0x0000000e)
PENDING_JOB_REASON_UNDEFINED
public static final int PENDING_JOB_REASON_UNDEFINED
There is no known reason why the job is pending. If additional reasons are added on newer Android versions, the system may return this reason to apps whose target SDK is not high enough to expect that reason.
Constant Value: 0 (0x00000000)
PENDING_JOB_REASON_USER
public static final int PENDING_JOB_REASON_USER
JobScheduler is respecting one of the user's actions (eg. force stop or adb shell commands) to defer this job.
Constant Value: 15 (0x0000000f)
RESULT_FAILURE
public static final int RESULT_FAILURE
Returned from schedule(android.app.job.JobInfo)
if a job wasn't scheduled successfully. Scheduling
can fail for a variety of reasons, including, but not limited to:
- an invalid parameter was supplied (eg. the run-time for your job is too short, or the
system can't resolve the requisite
JobService
in your package) - the app has too many jobs scheduled
- the app has tried to schedule too many jobs in a short amount of time
Constant Value: 0 (0x00000000)
RESULT_SUCCESS
public static final int RESULT_SUCCESS
Returned from schedule(android.app.job.JobInfo)
if this job has been successfully scheduled.
Constant Value: 1 (0x00000001)
Public constructors
JobScheduler
public JobScheduler ()
Public methods
canRunUserInitiatedJobs
public boolean canRunUserInitiatedJobs ()
Returns true
if the calling app currently holds the
Manifest.permission.RUN_USER_INITIATED_JOBS
permission, allowing it to run
user-initiated jobs.
Returns | |
---|---|
boolean |
cancel
public abstract void cancel (int jobId)
Cancel the specified job. If the job is currently executing, it is stopped
immediately and the return value from its JobService.onStopJob(JobParameters)
method is ignored.
Parameters | |
---|---|
jobId |
int : unique identifier for the job to be canceled, as supplied to
JobInfo.Builder(int, android.content.ComponentName) . |
cancelAll
public abstract void cancelAll ()
Cancel all jobs that have been scheduled in the current namespace by the calling application.
Starting with Android version Build.VERSION_CODES.UPSIDE_DOWN_CAKE
, this
will only cancel within the current namespace. If a namespace hasn't been explicitly set
with forNamespace(java.lang.String)
, then this will cancel jobs in the default namespace.
To cancel all jobs scheduled by the application,
use cancelInAllNamespaces()
instead.
cancelInAllNamespaces
public void cancelInAllNamespaces ()
Cancel all jobs that have been scheduled by the calling application, regardless of namespace.
enqueue
public abstract int enqueue (JobInfo job, JobWorkItem work)
Similar to schedule(JobInfo)
, but allows you to enqueue work for a new or existing
job. If a job with the same ID is already scheduled, it will be replaced with the
new JobInfo
, but any previously enqueued work will remain and be dispatched the
next time it runs. If a job with the same ID is already running, the new work will be
enqueued for it without stopping the job.
The work you enqueue is later retrieved through
JobParameters.dequeueWork
. Be sure to see there
about how to process work; the act of enqueueing work changes how you should handle the
overall lifecycle of an executing job.
It is strongly encouraged that you use the same JobInfo
for all work you
enqueue. This will allow the system to optimally schedule work along with any pending
and/or currently running work. If the JobInfo changes from the last time the job was
enqueued, the system will need to update the associated JobInfo, which can cause a disruption
in execution. In particular, this can result in any currently running job that is processing
previous work to be stopped and restarted with the new JobInfo.
It is recommended that you avoid using
JobInfo.Builder.setExtras(PersistableBundle)
or
JobInfo.Builder.setTransientExtras(Bundle)
with a JobInfo you are using to
enqueue work. The system will try to compare these extras with the previous JobInfo,
but there are situations where it may get this wrong and count the JobInfo as changing.
(That said, you should be relatively safe with a simple set of consistent data in these
fields.) You should never use JobInfo.Builder.setClipData(ClipData, int)
with
work you are enqueuing, since currently this will always be treated as a different JobInfo,
even if the ClipData contents are exactly the same.
Note: Scheduling a job can have a high cost, even if it's
rescheduling the same job and the job didn't execute, especially on platform versions before
version Build.VERSION_CODES.Q
. As such, the system may throttle calls to
this API if calls are made too frequently in a short amount of time.
Note: Prior to Android version
Build.VERSION_CODES.UPSIDE_DOWN_CAKE
, JobWorkItems could not be persisted.
Apps were not allowed to enqueue JobWorkItems with persisted jobs and the system would throw
an IllegalArgumentException
if they attempted to do so. Starting with
Build.VERSION_CODES.UPSIDE_DOWN_CAKE
,
JobWorkItems can be persisted alongside the hosting job.
However, Intents cannot be persisted. Set a PersistableBundle
using
JobWorkItem.Builder.setExtras(PersistableBundle)
for any information that needs
to be persisted.
Note: The JobService component needs to be enabled in order to successfully schedule a job.
Parameters | |
---|---|
job |
JobInfo : The job you wish to enqueue work for. See
JobInfo.Builder for more detail on the sorts of jobs
you can schedule.
This value cannot be null . |
work |
JobWorkItem : New work to enqueue. This will be available later when the job starts running.
This value cannot be null . |
Returns | |
---|---|
int |
the result of the enqueue request.
Value is RESULT_FAILURE , or RESULT_SUCCESS |
Throws | |
---|---|
IllegalArgumentException |
if the specified JobService doesn't exist or is
disabled. |
forNamespace
public JobScheduler forNamespace (String namespace)
Get a JobScheduler instance that is dedicated to a specific namespace. Any API calls using this instance will interact with jobs in that namespace, unless the API documentation says otherwise. Attempting to update a job scheduled in another namespace will not be possible but will instead create or update the job inside the current namespace. A JobScheduler instance dedicated to a namespace must be used to schedule or update jobs in that namespace.
Since leading and trailing whitespace can lead to hard-to-debug issues,
they will be trimmed
. An empty String (after trimming) is not allowed.
Parameters | |
---|---|
namespace |
String : This value cannot be null . |
Returns | |
---|---|
JobScheduler |
This value cannot be null . |
See also:
getAllPendingJobs
public abstract List<JobInfo> getAllPendingJobs ()
Retrieve all jobs that have been scheduled by the calling application.
Returns | |
---|---|
List<JobInfo> |
a list of all of the app's scheduled jobs. This includes jobs that are
currently started as well as those that are still waiting to run.
This value cannot be null . |
getNamespace
public String getNamespace ()
Get the namespace this JobScheduler instance is operating in. A null
value means
that the app has not specified a namespace for this instance, and it is therefore using the
default namespace.
Returns | |
---|---|
String |
getPendingJob
public abstract JobInfo getPendingJob (int jobId)
Look up the description of a scheduled job.
Parameters | |
---|---|
jobId |
int |
Returns | |
---|---|
JobInfo |
The JobInfo description of the given scheduled job, or null
if the supplied job ID does not correspond to any job. |
getPendingJobReason
public int getPendingJobReason (int jobId)
Returns a reason why the job is pending and not currently executing. If there are multiple reasons why a job may be pending, this will only return one of them.
API Note:
- To know all the potential reasons why the job may be pending,
use
getPendingJobReasons(int)
instead.
Parameters | |
---|---|
jobId |
int |
getPendingJobReasons
public int[] getPendingJobReasons (int jobId)
Returns potential reasons why the job with the given jobId
may be pending
and not currently executing.
The returned array will include ERROR(reasons/android.app.job.JobScheduler.PendingJobReason reasons)
composed of both
explicitly set constraints on the job and implicit constraints imposed by the system.
The results can be used to debug why a given job may not be currently executing.
Parameters | |
---|---|
jobId |
int |
getPendingJobReasonsHistory
public List<PendingJobReasonsInfo> getPendingJobReasonsHistory (int jobId)
For the given jobId
, returns a limited historical view of why the job may have
been pending execution. The returned list is composed of PendingJobReasonsInfo
objects, each of which include a timestamp since epoch along with an array of
unsatisfied constraints represented by ERROR(PendingJobReason constants/android.app.job.JobScheduler.PendingJobReason PendingJobReason constants)
.
These constants could either be explicitly set constraints on the job or implicit constraints imposed by the system due to various reasons. The results can be used to debug why a given job may have been pending execution.
If the only ERROR(PendingJobReason/android.app.job.JobScheduler.PendingJobReason PendingJobReason)
for the timestamp is
ERROR(PendingJobReason.PENDING_JOB_REASON_UNDEFINED/android.app.job.JobScheduler.PendingJobReason#PENDING_JOB_REASON_UNDEFINED PendingJobReason.PENDING_JOB_REASON_UNDEFINED)
, it could mean that
the job was ready to be executed at that point in time.
Note: there is no set interval for the timestamps in the returned list since constraint changes occur based on device status and various other factors.
Note: the pending job reasons history is not persisted across device reboots.
Parameters | |
---|---|
jobId |
int |
Returns | |
---|---|
List<PendingJobReasonsInfo> |
This value cannot be null . |
Throws | |
---|---|
IllegalArgumentException |
if the jobId is invalid. |
See also:
getPendingJobsInAllNamespaces
public Map<String, List<JobInfo>> getPendingJobsInAllNamespaces ()
Retrieve all jobs that have been scheduled by the calling application within the current namespace.
Returns | |
---|---|
Map<String, List<JobInfo>> |
a list of all of the app's scheduled jobs scheduled with the current namespace.
If a namespace hasn't been explicitly set with forNamespace(java.lang.String) ,
then this will return jobs in the default namespace.
This includes jobs that are currently started as well as those that are still waiting to run.
This value cannot be null . |
schedule
public abstract int schedule (JobInfo job)
Schedule a job to be executed. Will replace any currently scheduled job with the same
ID with the new information in the JobInfo
. If a job with the given ID is currently
running, it will be stopped.
Note: Scheduling a job can have a high cost, even if it's
rescheduling the same job and the job didn't execute, especially on platform versions before
version Build.VERSION_CODES.Q
. As such, the system may throttle calls to
this API if calls are made too frequently in a short amount of time.
Note: The JobService component needs to be enabled in order to successfully schedule a job.
Parameters | |
---|---|
job |
JobInfo : The job you wish scheduled. See
JobInfo.Builder for more detail on the sorts of jobs
you can schedule.
This value cannot be null . |
Returns | |
---|---|
int |
the result of the schedule request.
Value is RESULT_FAILURE , or RESULT_SUCCESS |
Throws | |
---|---|
IllegalArgumentException |
if the specified JobService doesn't exist or is
disabled. |