org.opencastproject.job.api

Class JobBarrier

java.lang.Object

org.opencastproject.job.api.JobBarrier

public final class JobBarrier
extends Object

This class is a utility implementation that will wait for all given jobs to change their status to either one of:

• Job.Status.FINISHED
• Job.Status.FAILED
• Job.Status.DELETED

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	JobBarrier.Result Result of a waiting operation on a certain number of jobs.

Field Summary

Fields

Modifier and Type	Field and Description
static long	DEFAULT_POLLING_INTERVAL Default polling interval is 5 seconds

Constructor Summary

Constructors

Constructor and Description
JobBarrier(Job waiter, ServiceRegistry registry) Creates a barrier without any jobs, using registry to poll for the outcome of the monitored jobs using the default polling interval DEFAULT_POLLING_INTERVAL.
JobBarrier(Job waiter, ServiceRegistry registry, Job... jobs) Creates a barrier for jobs, using registry to poll for the outcome of the monitored jobs using the default polling interval DEFAULT_POLLING_INTERVAL.
JobBarrier(Job waiter, ServiceRegistry registry, long pollingInterval) Creates a wrapper for job, using registry to poll for the job outcome.
JobBarrier(Job waiter, ServiceRegistry registry, long pollingInterval, Job... jobs) Creates a wrapper for job, using registry to poll for the job outcome.

Method Summary

Modifier and Type	Method and Description
void	addJob(Job job) Adds the job to the list of jobs to wait for.
JobBarrier.Result	getStatus() Returns the resulting status map.
JobBarrier.Result	waitForJobs() Waits for a status change and returns the new status.
JobBarrier.Result	waitForJobs(long timeout) Waits for a status change on all jobs and returns.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

DEFAULT_POLLING_INTERVAL

public static final long DEFAULT_POLLING_INTERVAL

Default polling interval is 5 seconds

See Also:

Constant Field Values

Constructor Detail

JobBarrier

public JobBarrier(Job waiter,
                  ServiceRegistry registry)

Creates a barrier without any jobs, using registry to poll for the outcome of the monitored jobs using the default polling interval DEFAULT_POLLING_INTERVAL. The waiter is the job which is waiting for the other jobs to finish. Use addJob(Job) to add jobs to monitor.

Parameters:

registry - the registry

waiter - the job waiting for the other jobs to finish

JobBarrier

public JobBarrier(Job waiter,
                  ServiceRegistry registry,
                  Job... jobs)

Creates a barrier for jobs, using registry to poll for the outcome of the monitored jobs using the default polling interval DEFAULT_POLLING_INTERVAL. The waiter is the job which is waiting for the other jobs to finish.

Parameters:

registry - the registry

jobs - the jobs to monitor

waiter - the job waiting for the other jobs to finish

JobBarrier

public JobBarrier(Job waiter,
                  ServiceRegistry registry,
                  long pollingInterval)

Creates a wrapper for job, using registry to poll for the job outcome. The waiter is the job which is waiting for the other jobs to finish.

Parameters:

registry - the registry

pollingInterval - the time in miliseconds between two polling operations

waiter - the job waiting for the other jobs to finish

JobBarrier

public JobBarrier(Job waiter,
                  ServiceRegistry registry,
                  long pollingInterval,
                  Job... jobs)

Creates a wrapper for job, using registry to poll for the job outcome. The waiter is the job which is waiting for the other jobs to finish.

Parameters:

jobs - the job to poll

registry - the registry

pollingInterval - the time in miliseconds between two polling operations

waiter - the job waiting for the other jobs to finish

Method Detail

waitForJobs

public JobBarrier.Result waitForJobs()

Waits for a status change and returns the new status.

Returns:

the status

waitForJobs

public JobBarrier.Result waitForJobs(long timeout)
                              throws JobCanceledException,
                                     IllegalStateException

Waits for a status change on all jobs and returns. If waiting for the status exceeds a certain limit, the method returns even if some or all of the jobs are not yet finished. The same is true if at least one of the jobs fails or gets stopped or deleted.

Parameters:

timeout - the maximum amount of time to wait

Throws:

IllegalStateException - if there are no jobs to wait for

JobCanceledException - if one of the jobs was canceled

addJob

public void addJob(Job job)
            throws IllegalStateException

Adds the job to the list of jobs to wait for. An IllegalStateException is thrown if the barrier has already been asked to wait for jobs by calling waitForJobs().

Parameters:

job - the job

Throws:

IllegalStateException - if the barrier already started waiting

getStatus

public JobBarrier.Result getStatus()

Returns the resulting status map.

Returns:

the status of the individual jobs