SingletonTask (Hibernate Search 6.1.8.Final)

java.lang.Object
- org.hibernate.search.engine.backend.orchestration.spi.SingletonTask

```
public final class SingletonTask
extends Object
```
A task that can be scheduled for a run and is guaranteed to never run concurrently, regardless of the thread pool it's submitted to.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static interface SingletonTask.Scheduler

static interface SingletonTask.Worker

Constructor Summary

Constructors
Constructor	Description
`SingletonTask(String name, SingletonTask.Worker worker, SingletonTask.Scheduler scheduler, FailureHandler failureHandler)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`CompletableFuture<?>`	`completion()`
`void`	`ensureScheduled()`	Ensures the task will run in the future.
`void`	`stop()`	Stop the task.
`String`	`toString()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Constructor Detail
  - SingletonTask
```
public SingletonTask(String name,
                     SingletonTask.Worker worker,
                     SingletonTask.Scheduler scheduler,
                     FailureHandler failureHandler)
```
- Method Detail
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - ensureScheduled
```
public void ensureScheduled()
```
    Ensures the task will run in the future.
    
    If the task is neither scheduled nor running, this schedules the task for execution.
    
    If the task is already scheduled but not running, this does nothing: the task remains scheduled.
    
    If the task is running: the task execution continues and will trigger re-scheduling when it finishes.
  - completion
```
public CompletableFuture<?> completion()
```
    Returns:
    
    A future that completes when all works submitted to the executor so far are completely executed. Works submitted to the executor after entering this method may delay the wait.
  - stop
```
public void stop()
```
    Stop the task.
    Callers must call this as the very last method on this object; any concurrent call may lead to unpredictable results.