Package org.quartz.core

Interface Scheduler

All Known Implementing Classes:
QuartzScheduler
public interface Scheduler
This is the main interface of a Quartz Scheduler.

A Scheduler maintains a registry of JobDetail s and Triggers. Once registered, the Scheduler is responsible for executing Job s when their associated Trigger s fire (when their scheduled time arrives).

Scheduler instances are produced by a SchedulerFactory. A scheduler that has already been created/initialized can be found and used through the same factory that produced it. After a Scheduler has been created, it is in "stand-by" mode, and must have its start() method called before it will fire any Job s.

Job s are to be created by the 'client program', by defining a class that implements the Job interface. JobDetail objects are then created (also by the client) to define a individual instances of the Job . JobDetail instances can then be registered with the Scheduler via the scheduleJob(JobDetail, Trigger) or addJob(JobDetail, boolean) method.

Trigger s can then be defined to fire individual Job instances based on given schedules. SimpleTrigger s are most useful for one-time firings, or firing at an exact moment in time, with N repeats with a given delay between them. CronTrigger s allow scheduling based on time of day, day of week, day of month, and month of year.

Job s and Trigger s have a name and group associated with them, which should uniquely identify them within a single Scheduler. The 'group' feature may be useful for creating logical groupings or categorizations of Jobs s and Triggerss. If you don't have need for assigning a group to a given Jobs of Triggers, then you can use the DEFAULT_GROUP constant defined on this interface.

Stored Job s can also be 'manually' triggered through the use of the triggerJob(String jobName, String jobGroup) function.

Client programs may also be interested in the 'listener' interfaces that are available from Quartz. The JobListener interface provides notifications of Job executions. The TriggerListener interface provides notifications of Trigger firings. The SchedulerListener interface provides notifications of Scheduler events and errors. Listeners can be associated with local schedulers through the ListenerManager interface.

The setup/configuration of a Scheduler instance is very customizable. Please consult the documentation distributed with Quartz.

Author:
James House, Sharada Jambula

  • Method Details

    • start

      void start() throws SchedulerException
      Starts the Scheduler's threads that fire Triggers. When a scheduler is first created it is in "stand-by" mode, and will not fire triggers. The scheduler can also be put into stand-by mode by calling the standby() method.

      The misfire/recovery process will be started, if it is the initial call to this method on this scheduler instance.

      Throws:
      SchedulerException - if shutdown() has been called, or there is an error within the Scheduler.

    • startDelayed

      void startDelayed(int seconds) throws SchedulerException
      Calls {#start()} after the indicated number of seconds. (This call does not block). This can be useful within applications that have initializers that create the scheduler immediately, before the resources needed by the executing jobs have been fully initialized.
      Throws:
      SchedulerException - if shutdown() has been called, or there is an error within the Scheduler.

    • isStarted

      boolean isStarted() throws SchedulerException
      Whether the scheduler has been started.

      Note: This only reflects whether start() has ever been called on this Scheduler, so it will return true even if the Scheduler is currently in standby mode or has been since shutdown.

      Throws:
      SchedulerException

    • standby

      void standby() throws SchedulerException
      Temporarily halts the Scheduler's firing of Triggers.

      When start() is called (to bring the scheduler out of stand-by mode), trigger misfire instructions will NOT be applied during the execution of the start() method - any misfires will be detected immediately afterward (by the JobStore's normal process).

      The scheduler is not destroyed, and can be re-started at any time.

      Throws:
      SchedulerException

    • isInStandbyMode

      boolean isInStandbyMode() throws SchedulerException
      Reports whether the Scheduler is in stand-by mode.
      Throws:
      SchedulerException

    • shutdown

      void shutdown() throws SchedulerException
      Halts the Scheduler's firing of Triggers, and cleans up all resources associated with the Scheduler.

      The scheduler cannot be re-started.

      Throws:
      SchedulerException

    • isShutdown

      boolean isShutdown() throws SchedulerException
      Reports whether the Scheduler has been shutdown.
      Throws:
      SchedulerException

    • getCurrentlyExecutingJobs

      List<JobExecutionContext> getCurrentlyExecutingJobs() throws SchedulerException
      Return a list of JobExecutionContext objects that represent all currently executing Jobs in this Scheduler instance.

      This method is not cluster aware. That is, it will only return Jobs currently executing in this Scheduler instance, not across the entire cluster.

      Note that the list returned is an 'instantaneous' snap-shot, and that as soon as it's returned, the true list of executing jobs may be different. Also please read the doc associated with JobExecutionContext- especially if you're using RMI.

      Throws:
      SchedulerException

    • getJobKeys

      Set<String> getJobKeys() throws SchedulerException
      Get the keys of all the JobDetails in the matching groups.
      Returns:
      Set of all keys matching
      Throws:
      SchedulerException - On error

    • setJobFactory

      void setJobFactory(JobFactory factory) throws SchedulerException
      Set the JobFactory that will be responsible for producing instances of Job classes.

      JobFactories may be of use to those wishing to have their application produce Job instances via some special mechanism, such as to give the opportunity for dependency injection.

      Throws:
      SchedulerException

    • getListenerManager

      ListenerManager getListenerManager() throws SchedulerException
      Get a reference to the scheduler's ListenerManager, through which listeners may be registered.
      Returns:
      the scheduler's ListenerManager
      Throws:
      SchedulerException - if the scheduler is not local

    • scheduleJob

      Date scheduleJob(JobDetail jobDetail, OperableTrigger trigger) throws SchedulerException
      Add the given JobDetail to the Scheduler, and associate the given OperableTrigger with it.

      If the given Trigger does not reference any Job, then it will be set to reference the Job passed with it into this method.

      Throws:
      SchedulerException - if the Job or Trigger cannot be added to the Scheduler, or there is an internal Scheduler error.

    • scheduleJob

      Date scheduleJob(OperableTrigger trigger) throws SchedulerException
      Schedule the given OperableTrigger with the Job identified by the Trigger's settings.
      Throws:
      SchedulerException - if the indicated Job does not exist, or the Trigger cannot be added to the Scheduler, or there is an internal Scheduler error.

    • rescheduleJob

      Date rescheduleJob(String triggerName, OperableTrigger newTrigger) throws SchedulerException
      Remove (delete) the OperableTrigger with the given key, and store the new given one - which must be associated with the same job (the new trigger must have the job name specified) - however, the new trigger need not have the same name as the old trigger.
      Parameters:
      triggerName - identity of the trigger to replace
      newTrigger - The new Trigger to be stored.
      Returns:
      null if a Trigger with the given name invalid input: '&' group was not found and removed from the store, otherwise the first fire time of the newly scheduled trigger.
      Throws:
      SchedulerException

    • addJob

      void addJob(JobDetail jobDetail) throws SchedulerException
      Add the given Job to the Scheduler - with no associated Trigger. The Job will be 'dormant' until it is scheduled with a Trigger, or Scheduler.triggerJob() is called for it.

      The Job must by definition be 'durable', if it is not, SchedulerException will be thrown.

      Throws:
      SchedulerException - if there is an internal Scheduler error, or if the Job is not durable, or a Job with the same name already exists, and replace is false.

    • triggerJob

      void triggerJob(String jobKey, JobDataMap data) throws SchedulerException
      Trigger the identified JobDetail (execute it now).
      Parameters:
      data - the (possibly null) JobDataMap to be associated with the trigger that fires the job immediately.
      Throws:
      SchedulerException

    • getTriggersOfJob

      List<Trigger> getTriggersOfJob(String jobKey) throws SchedulerException
      Get all Trigger s that are associated with the identified JobDetail.

      The returned Trigger objects will be snap-shots of the actual stored triggers. If you wish to modify a trigger, you must re-store the trigger afterward (e.g. see

      invalid @link 
      #rescheduleJob(TriggerKey, Trigger)
      ).
      Throws:
      SchedulerException

    • getJobDetail

      JobDetail getJobDetail(String jobKey) throws SchedulerException
      Get the JobDetail for the Job instance with the given key.

      The returned JobDetail object will be a snap-shot of the actual stored JobDetail. If you wish to modify the JobDetail, you must re-store the JobDetail afterward (e.g. see

      invalid @link 
      #addJob(JobDetail, boolean)
      ).
      Throws:
      SchedulerException

    • getTrigger

      Trigger getTrigger(String triggerKey) throws SchedulerException
      Get the Trigger instance with the given key.

      The returned Trigger object will be a snap-shot of the actual stored trigger. If you wish to modify the trigger, you must re-store the trigger afterward (e.g. see

      invalid @link 
      #rescheduleJob(TriggerKey, Trigger)
      ).
      Throws:
      SchedulerException

    • deleteJob

      void deleteJob(String jobKey) throws SchedulerException
      Delete the identified Job from the Scheduler - and any associated Trigger s.
      Throws:
      SchedulerException - if there is an internal Scheduler error.

    • unscheduleJob

      void unscheduleJob(String triggerKey) throws SchedulerException
      Remove the indicated Trigger from the scheduler.

      If the related job does not have any other triggers, and the job is not durable, then the job will also be deleted.

      Throws:
      SchedulerException

    • getCascadingClassLoadHelper

      CascadingClassLoadHelper getCascadingClassLoadHelper()