Package org.eclipse.core.runtime.jobs

Class Job

java.lang.Object
org.eclipse.core.runtime.PlatformObject
org.eclipse.core.internal.jobs.InternalJob
org.eclipse.core.runtime.jobs.Job
All Implemented Interfaces:
Comparable<org.eclipse.core.internal.jobs.InternalJob>, IAdaptable
Direct Known Subclasses:
org.eclipse.core.internal.resources.InternalWorkspaceJob, ProvisioningJob, UIJob
public abstract class Job extends org.eclipse.core.internal.jobs.InternalJob
Jobs are units of runnable work that can be scheduled to be run with the job manager. Once a job has completed, it can be scheduled to run again (jobs are reusable).

Jobs have a state that indicates what they are currently doing. When constructed, jobs start with a state value of NONE. When a job is scheduled to be run, it moves into the WAITING state. When a job starts running, it moves into the RUNNING state. When execution finishes (either normally or through cancelation), the state changes back to NONE.

A job can also be in the SLEEPING state. This happens if a user calls Job.sleep() on a waiting job, or if a job is scheduled to run after a specified delay. Only jobs in the WAITING state can be put to sleep. Sleeping jobs can be woken at any time using Job.wakeUp(), which will put the job back into the WAITING state.

Jobs can be assigned a priority that is used as a hint about how the job should be scheduled. There is no guarantee that jobs of one priority will be run before all jobs of lower priority. The javadoc for the various priority constants provide more detail about what each priority means. By default, jobs start in the LONG priority class.

Since:
3.0
See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final IStatus
    ASYNC_FINISH
    Job status return value that is used to indicate asynchronous job completion.
    static final int
    BUILD
    Job priority constant (value 40) for build jobs.
    static final int
    DECORATE
    Job priority constant (value 50) for decoration jobs.
    static final int
    INTERACTIVE
    Job priority constant (value 10) for interactive jobs.
    static final int
    LONG
    Job priority constant (value 30) for long-running background jobs.
    static final int
    NONE
    Job state code (value 0) indicating that a job is not currently sleeping, waiting, or running (i.e., the job manager doesn't know anything about the job).
    static final int
    RUNNING
    Job state code (value 4) indicating that a job is currently running
    static final int
    SHORT
    Job priority constant (value 20) for short background jobs.
    static final int
    SLEEPING
    Job state code (value 1) indicating that a job is sleeping.
    static final int
    WAITING
    Job state code (value 2) indicating that a job is waiting to run.

    Fields inherited from class org.eclipse.core.internal.jobs.InternalJob

    manager

  • Constructor Summary

    Constructors
    Constructor
    Description
    Job(String name)
    Creates a new job with the specified name.

  • Method Summary

    Modifier and Type
    Method
    Description
    final void
    addJobChangeListener(IJobChangeListener listener)
    Registers a job listener with this job Has no effect if an identical listener is already registered.
    boolean
    belongsTo(Object family)
    Returns whether this job belongs to the given family.
    final boolean
    cancel()
    Stops the job.
    protected void
    canceling()
    A hook method indicating that this job is running and cancel() is being called for the first time.
    static Job
    create(String name, ICoreRunnable runnable)
    Creates a new Job that will execute the provided runnable when it runs.
    static Job
    create(String name, IJobFunction function)
    Creates a new Job that will execute the provided function when it runs.
    static Job
    createSystem(String name, ICoreRunnable runnable)
    Creates a new system Job with the given name that will execute the provided runnable when it runs.
    static Job
    createSystem(String name, IJobFunction function)
    Creates a new system Job with the given name that will execute the provided function when it runs.
    final void
    done(IStatus result)
    Jobs that complete their execution asynchronously must indicate when they are finished by calling this method.
    final JobGroup
    getJobGroup()
    Returns the job group this job belongs to, or null if this job does not belongs to any group.
    static final IJobManager
    getJobManager()
    Returns the job manager.
    final String
    getName()
    Returns the human readable name of this job.
    final int
    getPriority()
    Returns the priority of this job.
    final Object
    getProperty(QualifiedName key)
    Returns the value of the property of this job identified by the given key, or null if this job has no such property.
    final IStatus
    getResult()
    Returns the result of this job's last run.
    final ISchedulingRule
    getRule()
    Returns the scheduling rule for this job.
    final int
    getState()
    Returns the state of the job.
    final Thread
    getThread()
    Returns the thread that this job is currently running in.
    final boolean
    isBlocking()
    Returns whether this job is blocking a higher priority non-system job from starting due to a conflicting scheduling rule.
    final boolean
    isSystem()
    Returns whether this job is a system job.
    final boolean
    isUser()
    Returns whether this job has been directly initiated by a UI end user.
    final void
    join()
    Waits until this job is finished.
    final boolean
    join(long timeoutMillis, IProgressMonitor monitor)
    Waits until either the job is finished or the given timeout has expired.
    final void
    removeJobChangeListener(IJobChangeListener listener)
    Removes a job listener from this job.
    protected abstract IStatus
    run(IProgressMonitor monitor)
    Executes this job.
    final void
    schedule()
    Schedules this job to be run.
    final void
    schedule(long delay)
    Schedules this job to be run after a specified delay.
    final void
    setJobGroup(JobGroup jobGroup)
    Sets the job group to which this job belongs.
    final void
    setName(String name)
    Changes the name of this job.
    final void
    setPriority(int priority)
    Sets the priority of the job.
    final void
    setProgressGroup(IProgressMonitor group, int ticks)
    Associates this job with a progress group.
    void
    setProperty(QualifiedName key, Object value)
    Sets the value of the property of this job identified by the given key.
    final void
    setRule(ISchedulingRule rule)
    Sets the scheduling rule to be used when scheduling this job.
    final void
    setSystem(boolean value)
    Sets whether or not this job is a system job.
    final void
    setThread(Thread thread)
    Sets the thread that this job is currently running in, or null if this job is not running or the thread is unknown.
    final void
    setUser(boolean value)
    Sets whether or not this job has been directly initiated by a UI end user.
    boolean
    shouldRun()
    Returns whether this job should be run.
    boolean
    shouldSchedule()
    Returns whether this job should be scheduled.
    final boolean
    sleep()
    Requests that this job be suspended.
    String
    toString()
    Returns a string representation of this job to be used for debugging purposes only.
    final void
    wakeUp()
    Puts this job immediately into the WAITING state so that it is eligible for immediate execution.
    final void
    wakeUp(long delay)
    Puts this job back into the WAITING state after the specified delay.
    Job
    yieldRule(IProgressMonitor monitor)
    Temporarily puts this Job back into WAITING state and relinquishes the job's scheduling rule so that any WAITING jobs that conflict with this job's scheduling rule have an opportunity to start.

    Methods inherited from class org.eclipse.core.internal.jobs.InternalJob

    compareTo

    Methods inherited from class org.eclipse.core.runtime.PlatformObject

    getAdapter

    Methods inherited from class java.lang.Object

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

  • Field Details

  • Constructor Details

    • Job

      public Job(String name)
      Creates a new job with the specified name. The job name is a human-readable value that is displayed to users. The name does not need to be unique, but it must not be null.
      Parameters:
      name - the name of the job.

  • Method Details

    • getJobManager

      public static final IJobManager getJobManager()
      Returns the job manager.
      Returns:
      the job manager
      Since:
      org.eclipse.core.jobs 3.2

    • create

      public static Job create(String name, IJobFunction function)
      Creates a new Job that will execute the provided function when it runs. Prefer using create(String, ICoreRunnable) as this does not require to call done on the monitor and relies on OperationCanceledException
      Parameters:
      name - The name of the job
      function - The function to execute
      Returns:
      A job that encapsulates the provided function
      Since:
      3.6
      See Also:

    • create

      public static Job create(String name, ICoreRunnable runnable)
      Creates a new Job that will execute the provided runnable when it runs.
      Parameters:
      name - the name of the job
      runnable - the runnable to execute
      Returns:
      a job that encapsulates the provided runnable
      Since:
      3.8
      See Also:

    • createSystem

      public static Job createSystem(String name, IJobFunction function)
      Creates a new system Job with the given name that will execute the provided function when it runs. Prefer using createSystem(String, ICoreRunnable) as this does not require to call done on the monitor and relies on OperationCanceledException
      Parameters:
      name - the name of the job
      function - The function to execute
      Returns:
      a job that encapsulates the provided function
      Since:
      3.10
      See Also:

    • createSystem

      public static Job createSystem(String name, ICoreRunnable runnable)
      Creates a new system Job with the given name that will execute the provided runnable when it runs.
      Parameters:
      name - the name of the job
      runnable - the runnable to execute
      Returns:
      a job that encapsulates the provided runnable
      Since:
      3.8
      See Also:

    • addJobChangeListener

      public final void addJobChangeListener(IJobChangeListener listener)
      Registers a job listener with this job Has no effect if an identical listener is already registered.
      Overrides:
      addJobChangeListener in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      listener - the listener to be added.

    • belongsTo

      public boolean belongsTo(Object family)
      Returns whether this job belongs to the given family. Job families are represented as objects that are not interpreted or specified in any way by the job manager. Thus, a job can choose to belong to any number of families.

      Clients may override this method. This default implementation always returns false. Overriding implementations must return false for families they do not recognize.

      Overrides:
      belongsTo in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      family - the job family identifier
      Returns:
      true if this job belongs to the given family, and false otherwise.

    • cancel

      public final boolean cancel()
      Stops the job. If the job is currently waiting, it will be removed from the queue. If the job is sleeping, it will be discarded without having a chance to resume and its sleeping state will be cleared. If the job is currently executing, it will be asked to stop but there is no guarantee that it will do so.
      Overrides:
      cancel in class org.eclipse.core.internal.jobs.InternalJob
      Returns:
      false if the job is currently running (and thus may not respond to cancelation), and true in all other cases.

    • canceling

      protected void canceling()
      A hook method indicating that this job is running and cancel() is being called for the first time.

      Subclasses may override this method to perform additional work when a cancelation request is made. This default implementation does nothing.

      Overrides:
      canceling in class org.eclipse.core.internal.jobs.InternalJob
      Since:
      3.3

    • done

      public final void done(IStatus result)
      Jobs that complete their execution asynchronously must indicate when they are finished by calling this method. This method must not be called by a job that has not indicated that it is executing asynchronously.

      This method must not be called from within the scope of a job's run method. Jobs should normally indicate completion by returning an appropriate status from the run method. Jobs that return a status of ASYNC_FINISH from their run method must later call done to indicate completion.

      Overrides:
      done in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      result - a status object indicating the result of the job's execution.
      See Also:

    • getName

      public final String getName()
      Returns the human readable name of this job. The name is never null.
      Overrides:
      getName in class org.eclipse.core.internal.jobs.InternalJob
      Returns:
      the name of this job

    • getPriority

      public final int getPriority()
      Returns the priority of this job. The priority is used as a hint when the job is scheduled to be run.
      Overrides:
      getPriority in class org.eclipse.core.internal.jobs.InternalJob
      Returns:
      the priority of the job. One of INTERACTIVE, SHORT, LONG, BUILD, or DECORATE.

    • getProperty

      public final Object getProperty(QualifiedName key)
      Returns the value of the property of this job identified by the given key, or null if this job has no such property.
      Overrides:
      getProperty in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      key - the name of the property
      Returns:
      the value of the property, or null if this job has no such property
      See Also:

    • getResult

      public final IStatus getResult()
      Returns the result of this job's last run.
      Overrides:
      getResult in class org.eclipse.core.internal.jobs.InternalJob
      Returns:
      the result of this job's last run, or null if this job has never finished running.

    • getRule

      public final ISchedulingRule getRule()
      Returns the scheduling rule for this job. Returns null if this job has no scheduling rule.
      Overrides:
      getRule in class org.eclipse.core.internal.jobs.InternalJob
      Returns:
      the scheduling rule for this job, or null.
      See Also:

    • getState

      public final int getState()
      Returns the state of the job. Result will be one of:
      • Job.RUNNING - if the job is currently running.
      • Job.WAITING - if the job is waiting to be run.
      • Job.SLEEPING - if the job is sleeping.
      • Job.NONE - in all other cases.

      Note that job state is inherently volatile, and in most cases clients cannot rely on the result of this method being valid by the time the result is obtained. For example, if getState returns RUNNING, the job may have actually completed by the time the getState method returns. All clients can infer from invoking this method is that the job was recently in the returned state.

      Overrides:
      getState in class org.eclipse.core.internal.jobs.InternalJob
      Returns:
      the job state

    • getThread

      public final Thread getThread()
      Returns the thread that this job is currently running in.
      Overrides:
      getThread in class org.eclipse.core.internal.jobs.InternalJob
      Returns:
      the thread this job is running in, or null if this job is not running or the thread is unknown.

    • getJobGroup

      public final JobGroup getJobGroup()
      Returns the job group this job belongs to, or null if this job does not belongs to any group.
      Overrides:
      getJobGroup in class org.eclipse.core.internal.jobs.InternalJob
      Returns:
      the job group this job belongs to, or null.
      Since:
      3.7
      See Also:

    • isBlocking

      public final boolean isBlocking()
      Returns whether this job is blocking a higher priority non-system job from starting due to a conflicting scheduling rule. Returns false if this job is not running, or is not blocking a higher priority non-system job.
      Overrides:
      isBlocking in class org.eclipse.core.internal.jobs.InternalJob
      Returns:
      true if this job is blocking a higher priority non-system job, and false otherwise.
      See Also:

    • isSystem

      public final boolean isSystem()
      Returns whether this job is a system job. System jobs are typically not revealed to users in any UI presentation of jobs. Other than their UI presentation, system jobs act exactly like other jobs. If this value is not explicitly set, jobs are treated as non-system jobs. The default value is false.
      Overrides:
      isSystem in class org.eclipse.core.internal.jobs.InternalJob
      Returns:
      true if this job is a system job, and false otherwise.
      See Also:

    • isUser

      public final boolean isUser()
      Returns whether this job has been directly initiated by a UI end user. These jobs may be presented differently in the UI. The default value is false.
      Overrides:
      isUser in class org.eclipse.core.internal.jobs.InternalJob
      Returns:
      true if this job is a user-initiated job, and false otherwise.
      See Also:

    • join

      public final void join() throws InterruptedException
      Waits until this job is finished. This method will block the calling thread until the job has finished executing, or until this thread has been interrupted. If the job has not been scheduled, this method returns immediately. A job must not be joined from within the scope of its run method.

      If this method is called on a job that reschedules itself from within the run method, the join will return at the end of the first execution. In other words, join will return the first time this job exits the RUNNING state, or as soon as this job enters the NONE state.

      If this method is called while the job manager is suspended, this job will only be joined if it is already running; if this job is waiting or sleeping, this method returns immediately.

      Note that there is a deadlock risk when using join. If the calling thread owns a lock or object monitor that the joined thread is waiting for, deadlock will occur.

      Joining on another job belonging to the same group is not allowed if the group enforces throttling due to the potential for deadlock. For example, when the maximum threads allowed is set to 1 and a currently running Job A issues a join on another Job B belonging to its own job group, A waits indefinitely for its join to finish, but B never gets to run. To avoid that an IllegalStateException is thrown when a job tries to join another job belonging to the same job group. Joining another job belonging to the same group is allowed when the job group does not enforce throttling (JobGroup#getMaxThreads is zero).

      Calling this method is equivalent to calling join(0, null) and it is recommended to use the other join method with timeout and progress monitor as that will provide more control over the join operation.

      Overrides:
      join in class org.eclipse.core.internal.jobs.InternalJob
      Throws:
      InterruptedException - if this thread is interrupted while waiting
      IllegalStateException - when a job tries to join on itself or join on another job belonging to the same job group and the group is configured with non zero maximum threads allowed.
      See Also:

    • join

      public final boolean join(long timeoutMillis, IProgressMonitor monitor) throws InterruptedException, OperationCanceledException
      Waits until either the job is finished or the given timeout has expired. This method will block the calling thread until the job has finished executing, or the given timeout is expired, or the given progress monitor is canceled by the user or the calling thread is interrupted. If the job has not been scheduled, this method returns immediately. A job must not be joined from within the scope of its run method.

      If this method is called on a job that reschedules itself from within the run method, the join will return at the end of the first execution. In other words, join will return the first time this job exits the RUNNING state, or as soon as this job enters the NONE state.

      If this method is called while the job manager is suspended, this job will only be joined if it is already running; if this job is waiting or sleeping, this method returns immediately.

      Note that there is a deadlock risk when using join. If the calling thread owns a lock or object monitor that the joined thread is waiting for and the timeout is set zero (i.e no timeout), deadlock will occur.

      Joining on another job belonging to the same group is not allowed if the timeout is set to zero and the group enforces throttling due to the potential for deadlock. For example, when the maximum threads allowed is set to 1 and a currently running Job A issues a join with no timeout on another Job B belonging to its own job group, A waits indefinitely for its join to finish, but B never gets to run. To avoid that an IllegalStateException is thrown when a job tries to join (with no timeout) another job belonging to the same job group. Joining another job belonging to the same group is allowed when either the job group does not enforce throttling (JobGroup#getMaxThreads is zero) or a non zero timeout value is provided.

      Throws an OperationCanceledException when the given progress monitor is canceled. Canceling the monitor does not cancel the job and, if required, the job may be canceled explicitly using the cancel() method.

      Overrides:
      join in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      timeoutMillis - the maximum amount of time to wait for the join to complete, or zero for no timeout.
      monitor - the progress monitor that can be used to cancel the join operation, or null if cancellation is not required. No progress is reported on this monitor.
      Returns:
      true when the job completes, or false when the operation is not completed within the given time.
      Throws:
      InterruptedException - if this thread is interrupted while waiting
      IllegalStateException - when a job tries to join on itself or join with no timeout on another job belonging to the same job group and the group is configured with non-zero maximum threads allowed.
      OperationCanceledException - if the progress monitor is canceled while waiting
      Since:
      3.7
      See Also:

    • removeJobChangeListener

      public final void removeJobChangeListener(IJobChangeListener listener)
      Removes a job listener from this job. Has no effect if an identical listener is not already registered.
      Overrides:
      removeJobChangeListener in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      listener - the listener to be removed

    • run

      protected abstract IStatus run(IProgressMonitor monitor)
      Executes this job. Returns the result of the execution.

      The provided monitor can be used to report progress and respond to cancellation. If the progress monitor has been canceled, the job should finish its execution at the earliest convenience and return a result status of severity IStatus.CANCEL. The singleton cancel status Status.CANCEL_STATUS can be used for this purpose. The monitor is only valid for the duration of the invocation of this method.

      This method must not be called directly by clients. Clients should call schedule, which will in turn cause this method to be called.

      Jobs can optionally finish their execution asynchronously (in another thread) by returning a result status of ASYNC_FINISH. Jobs that finish asynchronously must specify the execution thread by calling setThread, and must indicate when they are finished by calling the method done.

      Specified by:
      run in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      monitor - the monitor to be used for reporting progress and responding to cancelation. The monitor is never null
      Returns:
      resulting status of the run. The result must not be null
      See Also:

    • schedule

      public final void schedule()
      Schedules this job to be run. The job is added to a queue of waiting jobs, and will be run when it arrives at the beginning of the queue.

      This is a convenience method, fully equivalent to schedule(0L).

      See Also:

    • schedule

      public final void schedule(long delay)
      Schedules this job to be run after a specified delay. The job is put in the SLEEPING state until the specified delay has elapsed, after which the job is added to a queue of WAITING jobs. Once the job arrives at the beginning of the queue, it will be run at the first available opportunity.

      Jobs of equal priority and delay with conflicting scheduling rules are guaranteed to run in the order they are scheduled. No guarantees are made about the relative execution order of jobs with unrelated or null scheduling rules, or different priorities.

      If this job is currently running, it will be rescheduled with the specified delay as soon as it finishes. If this method is called multiple times while the job is running, the job will still only be rescheduled once, with the most recent delay value that was provided.

      Scheduling a job that is waiting or sleeping has no effect.

      Overrides:
      schedule in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      delay - a time delay in milliseconds before the job should run
      See Also:

    • setName

      public final void setName(String name)
      Changes the name of this job. If the job is currently running, waiting, or sleeping, the new job name may not take effect until the next time the job is scheduled.

      The job name is a human-readable value that is displayed to users. The name does not need to be unique, but it must not be null.

      Overrides:
      setName in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      name - the name of the job.

    • setPriority

      public final void setPriority(int priority)
      Sets the priority of the job. This will not affect the execution of a running job, but it will affect how the job is scheduled while it is waiting to be run.
      Overrides:
      setPriority in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      priority - the new job priority. One of INTERACTIVE, SHORT, LONG, BUILD, or DECORATE.

    • setProgressGroup

      public final void setProgressGroup(IProgressMonitor group, int ticks)
      Associates this job with a progress group. Progress feedback on this job's next execution will be displayed together with other jobs in that group. The provided monitor must be a monitor created by the method IJobManager.createProgressGroup and must have at least ticks units of available work.

      The progress group must be set before the job is scheduled. The group will be used only for a single invocation of the job's run method, after which any association of this job to the group will be lost.

      Overrides:
      setProgressGroup in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      group - The progress group to use for this job
      ticks - the number of work ticks allocated from the parent monitor, or IProgressMonitor.UNKNOWN
      See Also:

    • setProperty

      public void setProperty(QualifiedName key, Object value)
      Sets the value of the property of this job identified by the given key. If the supplied value is null, the property is removed from this resource.

      Properties are intended to be used as a caching mechanism by ISV plug-ins. They allow key-object associations to be stored with a job instance. These key-value associations are maintained in memory (at all times), and the information is never discarded automatically.

      The qualifier part of the property name must be the unique identifier of the declaring plug-in (e.g. "com.example.plugin").

      Overrides:
      setProperty in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      key - the qualified name of the property
      value - the value of the property, or null if the property is to be removed
      See Also:

    • setRule

      public final void setRule(ISchedulingRule rule)
      Sets the scheduling rule to be used when scheduling this job. This method must be called before the job is scheduled.
      Overrides:
      setRule in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      rule - the new scheduling rule, or null if the job should have no scheduling rule
      See Also:

    • setSystem

      public final void setSystem(boolean value)
      Sets whether or not this job is a system job. System jobs are typically not revealed to users in any UI presentation of jobs. Other than their UI presentation, system jobs act exactly like other jobs. If this value is not explicitly set, jobs are treated as non-system jobs. This method must be called before the job is scheduled.
      Overrides:
      setSystem in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      value - true if this job should be a system job, and false otherwise.
      See Also:

    • setUser

      public final void setUser(boolean value)
      Sets whether or not this job has been directly initiated by a UI end user. These jobs may be presented differently in the UI. This method must be called before the job is scheduled.
      Overrides:
      setUser in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      value - true if this job is a user-initiated job, and false otherwise.
      See Also:

    • setThread

      public final void setThread(Thread thread)
      Sets the thread that this job is currently running in, or null if this job is not running or the thread is unknown.

      Jobs that use the ASYNC_FINISH return code should tell the job what thread it is running in. This is used to prevent deadlocks.

      Overrides:
      setThread in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      thread - the thread that this job is running in.
      See Also:

    • setJobGroup

      public final void setJobGroup(JobGroup jobGroup)
      Sets the job group to which this job belongs. This method must be called before the job is scheduled, otherwise an IllegalStateException is thrown.
      Overrides:
      setJobGroup in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      jobGroup - the group to which this job belongs to, or null if this job does not belongs to any group.
      Since:
      3.7
      See Also:

    • shouldRun

      public boolean shouldRun()
      Returns whether this job should be run. If false is returned, this job will be discarded by the job manager without running.

      This method is called immediately prior to calling the job's run method, so it can be used for last minute precondition checking before a job is run. This method must not attempt to schedule or change the state of any other job.

      Clients may override this method. This default implementation always returns true.

      Returns:
      true if this job should be run and false otherwise

    • shouldSchedule

      public boolean shouldSchedule()
      Returns whether this job should be scheduled. If false is returned, this job will be discarded by the job manager without being added to the queue.

      This method is called immediately prior to adding the job to the waiting job queue.,so it can be used for last minute precondition checking before a job is scheduled.

      Clients may override this method. This default implementation always returns true.

      Overrides:
      shouldSchedule in class org.eclipse.core.internal.jobs.InternalJob
      Returns:
      true if the job manager should schedule this job and false otherwise

    • sleep

      public final boolean sleep()
      Requests that this job be suspended. If the job is currently waiting to be run, it will be removed from the queue move into the SLEEPING state. The job will remain asleep until either resumed or canceled. If this job is not currently waiting to be run, this method has no effect.

      Sleeping jobs can be resumed using wakeUp.

      Overrides:
      sleep in class org.eclipse.core.internal.jobs.InternalJob
      Returns:
      false if the job is currently running (and thus cannot be put to sleep), and true in all other cases
      See Also:

    • toString

      public String toString()
      Returns a string representation of this job to be used for debugging purposes only.
      Overrides:
      toString in class org.eclipse.core.internal.jobs.InternalJob
      Since:
      org.eclipse.core.jobs 3.5

    • wakeUp

      public final void wakeUp()
      Puts this job immediately into the WAITING state so that it is eligible for immediate execution. If this job is not currently sleeping, the request is ignored.

      This is a convenience method, fully equivalent to wakeUp(0L).

      See Also:

    • wakeUp

      public final void wakeUp(long delay)
      Puts this job back into the WAITING state after the specified delay. This is equivalent to canceling the sleeping job and rescheduling with the given delay. If this job is not currently sleeping, the request is ignored.
      Overrides:
      wakeUp in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      delay - the number of milliseconds to delay
      See Also:

    • yieldRule

      public Job yieldRule(IProgressMonitor monitor)
      Temporarily puts this Job back into WAITING state and relinquishes the job's scheduling rule so that any WAITING jobs that conflict with this job's scheduling rule have an opportunity to start. This method will wait until the rule this job held prior to invoking this method is re-acquired. This method has no effect and returns null if there are no WAITING jobs that conflict with this job's scheduling rule.

      Note: If this job has acquired any other locks, implicit or explicit, they will not be released. This may increase the risk of deadlock, so this method should only be used when it is known that the environment is safe.

      This method must be invoked by this job's Thread, and only when it is RUNNING state.

      Overrides:
      yieldRule in class org.eclipse.core.internal.jobs.InternalJob
      Parameters:
      monitor - a progress monitor, or null if progress reporting is not desired. Cancellation attempts will be ignored.
      Returns:
      The Job that was WAITING, and blocked by this Job (at the time this method was invoked) that was unblocked and allowed a chance to run, or null if no jobs were unblocked. Note: it is not guaranteed that this Job resume immediately if other conflicting jobs are also waiting after the unblocked job ends.
      Since:
      org.eclipse.core.jobs 3.5
      See Also: