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## org.quartz
Interface InterruptableJob

All Superinterfaces:
  Job

    public interface InterruptableJob

extends Job

The interface to be implemented by ``Job`s` that provide a mechanism for having their execution interrupted. It is NOT a requirement for jobs to implement this interface - in fact, for most people, none of their jobs will.

Interrupting a `Job` is very analogous in concept and challenge to normal interruption of a `Thread` in Java.

The means of actually interrupting the Job must be implemented within the `Job` itself (the `interrupt()` method of this interface is simply a means for the scheduler to inform the `Job` that a request has been made for it to be interrupted). The mechanism that your jobs use to interrupt themselves might vary between implementations. However the principle idea in any implementation should be to have the body of the job's `execute(..)` periodically check some flag to see if an interruption has been requested, and if the flag is set, somehow abort the performance of the rest of the job's work. An example of interrupting a job can be found in the java source for the class `org.quartz.examples.DumbInterruptableJob`. It is legal to use some combination of `wait()` and `notify()` synchronization within `interrupt()` and `execute(..)` in order to have the `interrupt()` method block until the `execute(..)` signals that it has noticed the set flag.

If the Job performs some form of blocking I/O or similar functions, you may want to consider having the `Job.execute(..)` method store a reference to the calling `Thread` as a member variable. Then the Implementation of this interfaces `interrupt()` method can call `interrupt()` on that Thread. Before attempting this, make sure that you fully understand what `java.lang.Thread.interrupt()` does and doesn't do. Also make sure that you clear the Job's member reference to the Thread when the execute(..) method exits (preferably in a `finally` block.

See Example 7 (org.quartz.examples.example7.DumbInterruptableJob) for a simple implementation demonstration.

Author:
  James House
See Also:
  `Job`, `StatefulJob`, `Scheduler.interrupt(String, String)`

Method Summary
`void` | `interrupt()` Called by the ``Scheduler`` when a user interrupts the `Job`.

Methods inherited from interface org.quartz.Job
`execute`

Method Detail

### interrupt

    void interrupt()
                   throws UnableToInterruptJobException

  Called by the ``Scheduler`` when a user interrupts the `Job`.

  Throws:
    `UnableToInterruptJobException` - if there is an exception while interrupting the job.

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