Type Parameters:: T - the result type

All Superinterfaces:: Supplier<T>

Enclosing class:: StructuredTaskScope^PREVIEW<T>

public static sealed interface StructuredTaskScope.Subtask<T> extends Supplier<T>

Subtask is a preview API of the Java platform.

Programs can only use Subtask when preview features are enabled.

Preview features may be removed in a future release, or upgraded to permanent features of the Java platform.

Represents a subtask forked with StructuredTaskScope.fork(Callable)^PREVIEW.

Since:: 21

Nested Class Summary

Nested Classes

Modifier and Type

Interface

Description

static enum

StructuredTaskScope.Subtask.State^PREVIEW

Preview.

Represents the state of a subtask.
Method Summary

Modifier and Type

Method

Description

Throwable

exception()

Returns the exception thrown by the subtask.

T

get()

Returns the result of the subtask.

StructuredTaskScope.Subtask.State^PREVIEW

state()

Returns the state of the subtask.

Callable<? extends T>

task()

Returns the value returning task provided to the fork method.

Method Details
- task
  
  Callable<? extends T> task()
  
  Returns the value returning task provided to the fork method.
  
  API Note:
  
  Task objects with unique identity may be used for correlation by implementations of handleComplete^PREVIEW.
  
  Returns:
  
  the value returning task provided to the fork method
- state
  
  StructuredTaskScope.Subtask.State^PREVIEW state()
  
  Returns the state of the subtask.
  
  Returns:
  
  the state of the subtask
- get
  
  T get()
  
  Returns the result of the subtask.
  To ensure correct usage, if the scope owner forks^PREVIEW a subtask, then it must join (with join^PREVIEW or joinUntil^PREVIEW) before it can obtain the result of the subtask.
  Specified by:
  
  get in interface Supplier<T>
  
  Returns:
  
  the possibly-null result
  
  Throws:
  
  IllegalStateException - if the subtask has not completed, did not complete successfully, or the current thread is the task scope owner and did not join after forking
  
  See Also:
  
  StructuredTaskScope.Subtask.State.SUCCESS^PREVIEW
- exception
  
  Throwable exception()
  
  Returns the exception thrown by the subtask.
  To ensure correct usage, if the scope owner forks^PREVIEW a subtask, then it must join (with join^PREVIEW or joinUntil^PREVIEW) before it can obtain the exception thrown by the subtask.
  Returns:
  
  the exception thrown by the subtask
  
  Throws:
  
  IllegalStateException - if the subtask has not completed, completed with a result, or the current thread is the task scope owner and did not join after forking
  
  See Also:
  
  StructuredTaskScope.Subtask.State.FAILED^PREVIEW

Interface StructuredTaskScope.Subtask<T>

Nested Class Summary

Method Summary

Method Details

task

state

get

exception