Module page.codeberg.friedolyn.Friedolyn

Package page.codeberg.friedolyn.util

Class Task<ResultType>

java.lang.Object

page.codeberg.friedolyn.util.Task<ResultType>

Type Parameters:

ResultType - The class of the end product that the action executed generates.

All Implemented Interfaces:

Runnable

Direct Known Subclasses:

Client.FetchPersonalData, ContactController.OpenContactReplyDialogTask, ContactController.SubmitTask, FriedolinClient.FetchClearname, FriedolinClient.FetchEmailAddress, FriedolinClient.Login, KeePassXC.AssociateAndLoginTask

public abstract class Task<ResultType>
extends Object
implements Runnable

Represents an action that is executed asynchronously and that can only be run once. Use a Task.TaskListener to subscribe to status updates of the action's progress.

See Also:

• run()
• cancel()
• getResult()
• registerListener(TaskListener)

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	Task.CancelListener	A subscriber exclusively interested in the cancellation of the action, but in no other information.
static interface	Task.FailureListener<ResultType>	A subscriber exclusively interested in the failure and the result of the action, but in no other information.
static interface	Task.ProgressListener	A subscriber exclusively interested in progress updates of the action, but in no other information.
static interface	Task.SuccessListener<ResultType>	A subscriber exclusively interested in the success and the result of the action, but in no other information.
static class	Task.TaskListener<ResultType>	A subscriber that is interested in status updates of the action's progress.

Constructor Summary

Constructors

Constructor	Description
Task()

Method Summary

Modifier and Type	Method	Description
abstract void	cancel()	Prematurely terminates the action.
abstract @NonNull Optional<Result<ResultType>>	getResult()
abstract void	registerListener(@NonNull Task.TaskListener<ResultType> taskListener)	Adds a subscriber that is interested in status updates of the action's progress.
abstract boolean	removeListener(@NonNull Task.TaskListener<ResultType> taskListener)	Removes a subscriber that was previously added to receive status updates of the action's progress.
abstract void	run()	Begins the execution of the action.
void	setOnCancelled(@NonNull Task.CancelListener cancelListener)	Adds a Task.TaskListener that is exclusively interested in the premature forceful termination of the action.
void	setOnFailed(@NonNull Task.FailureListener<ResultType> failureListener)	Adds a Task.TaskListener that is exclusively interested in the failure and the possible result of the action.
void	setOnProgressUpdate(@NonNull Task.ProgressListener progressListener)	Adds a Task.TaskListener that is exclusively interested in progress updates of the action.
void	setOnSucceeded(@NonNull Task.SuccessListener<ResultType> successListener)	Adds a Task.TaskListener that is exclusively interested in the success and the result of the action.

Methods inherited from class java.lang.Object

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

Constructor Details

Task

public Task()

Method Details

setOnProgressUpdate

public void setOnProgressUpdate(@NonNull
 @NonNull Task.ProgressListener progressListener)

Adds a Task.TaskListener that is exclusively interested in progress updates of the action. Does NOT remove or replace any existing listeners.

Parameters:

progressListener - What to do when progress has been made executing the task. Will be called by Task.ProgressListener.onProgressUpdate(int, int).

See Also:

• Task.TaskListener.from(ProgressListener)

setOnSucceeded

public void setOnSucceeded(@NonNull
 @NonNull Task.SuccessListener<ResultType> successListener)

Adds a Task.TaskListener that is exclusively interested in the success and the result of the action. Does NOT remove or replace any existing listeners.

Parameters:

successListener - What to do when the action has succeeded. Will be called by Task.SuccessListener.onSucceeded(Object).

See Also:

• Task.TaskListener.from(SuccessListener)

setOnFailed

public void setOnFailed(@NonNull
 @NonNull Task.FailureListener<ResultType> failureListener)

Adds a Task.TaskListener that is exclusively interested in the failure and the possible result of the action. Does NOT remove or replace any existing listeners.

Parameters:

failureListener - What to do when the action has failed. Will be called by Task.FailureListener.onFailed(Optional).

See Also:

• Task.TaskListener.from(FailureListener)

setOnCancelled

public void setOnCancelled(@NonNull
 @NonNull Task.CancelListener cancelListener)

Adds a Task.TaskListener that is exclusively interested in the premature forceful termination of the action. Does NOT remove or replace any existing listeners.

Parameters:

cancelListener - What to do when the action has been cancelled. Will be called by Task.CancelListener.onCancelled().

See Also:

• Task.TaskListener.from(CancelListener)

registerListener

public abstract void registerListener(@NonNull
 @NonNull Task.TaskListener<ResultType> taskListener)

Adds a subscriber that is interested in status updates of the action's progress. Does NOT remove or replace any existing listeners.

Parameters:

taskListener - The subscriber that wants to be informed about the progress of the action.

See Also:

• removeListener(TaskListener)

removeListener

public abstract boolean removeListener(@NonNull
 @NonNull Task.TaskListener<ResultType> taskListener)

Removes a subscriber that was previously added to receive status updates of the action's progress.

Parameters:

taskListener - The subscriber that no longer wants to be informed about the progress of the action. Must be the exact same reference that was previously registered.

Returns:

true if the subscriber was removed, false if it hadn't been registered in the first place.

See Also:

• registerListener(TaskListener)

run

public abstract void run()
                  throws IllegalStateException

Begins the execution of the action. The action will run in the same thread that it was envoked from. Use cancel() to prematurely terminate the action. The end product of the action can be retrieved using getResult().

Specified by:

run in interface Runnable

Throws:

IllegalStateException - If the action had been started before (each task can only be run once).

cancel

public abstract void cancel()
                     throws IllegalStateException

Prematurely terminates the action. The action will be stopped as soon as possible, but it may not be immediate, depending on the implementation.

Throws:

IllegalStateException - If the action had not been started before or if it has already finished.

getResult

@NonNull
public abstract @NonNull Optional<Result<ResultType>> getResult()

Returns:

The end product generated by the action. Empty if the action has not finished yet. The presence of Result.getResult() does NOT indicate success. Only Result.getSuccess() can be used to determine success or failure.