LazyFutureTask (Sosy-Lab Common Library)

java.lang.Object
- java.util.concurrent.FutureTask<V>
- - org.sosy_lab.common.LazyFutureTask<V>

All Implemented Interfaces:

Runnable, Future<V>, RunnableFuture<V>
```
public class LazyFutureTask<V>
extends FutureTask<V>
```
Future implementation that can be used when a task should be executed only lazily at the first time get() is called. I.e., it is not guaranteed that the task is run at all, but it is called at most once.
Execution of the task happens in the caller's thread, a little bit similar to the use of MoreExecutors.newDirectExecutorService(), however, it is executed on the thread calling get() and not on the thread calling ExecutorService.submit(Callable).
Important: Calling get(long, TimeUnit) is not supported and will always throw UnsupportedOperationException.
Canceling this future works as expected.

Constructor Summary

Constructors
Constructor Description

LazyFutureTask(Runnable pRunnable, @Nullable V pResult)

LazyFutureTask(Callable<V> pCallable)

Method Summary

All Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method	Description
`@Nullable V`	`get()`
`V`	`get(long pTimeout, TimeUnit pUnit)`	Deprecated. Unsupported operation.
`void`	`run()`

Methods inherited from class java.util.concurrent.FutureTask
cancel, done, isCancelled, isDone, runAndReset, set, setException, toString

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

- Constructor Detail
  - LazyFutureTask
```
public LazyFutureTask(Callable<V> pCallable)
```
  - LazyFutureTask
```
public LazyFutureTask(Runnable pRunnable,
                      @Nullable V pResult)
```
- Method Detail
  - run
```
public void run()
```
    Specified by:
    
    run in interface Runnable
    
    Specified by:
    
    run in interface RunnableFuture<V>
    
    Overrides:
    
    run in class FutureTask<V>
  - get
```
public @Nullable V get()
                throws InterruptedException,
                       ExecutionException
```
    Specified by:
    
    get in interface Future<V>
    
    Overrides:
    
    get in class FutureTask<V>
    
    Throws:
    
    InterruptedException
    
    ExecutionException
  - get
```
@Deprecated
public V get(long pTimeout,
             TimeUnit pUnit)
```
    Deprecated.
    Unsupported operation.
    
    Specified by:
    
    get in interface Future<V>
    
    Overrides:
    
    get in class FutureTask<V>
    
    Throws:
    
    UnsupportedOperationException - Always