- Type Parameters:
V
- the type of object returned by the Service
- All Implemented Interfaces:
Worker<V>
,EventTarget
- Direct Known Subclasses:
ScheduledService
A Service
is a non-visual component encapsulating the information required
to perform some work on one or more background threads. As part of the
JavaFX UI library, the Service
knows about the JavaFX Application thread
and is designed to relieve the application developer from the burden
of managing multithreaded code that interacts with the user interface. As
such, all of the methods and state on the Service
are intended to be
invoked exclusively from the JavaFX Application thread. The only exception
to this is when initially configuring a Service
, which may safely be done
from any thread, and initially starting a Service
, which may also safely
be done from any thread. However, once the Service
has been initialized and
started, it may only thereafter be used from the FX thread.
A Service
creates and manages a Task
that performs the work
on the background thread.
Service implements Worker
. As such, you can observe the state of
the background task and optionally cancel it. Service is a reusable
Worker, meaning that it can be reset and restarted. Due to this, a Service
can be constructed declaratively and restarted on demand.
Once a Service
is started, it will schedule its Task
and listen for
changes to the state of the Task
. A Task
does not hold a reference to the
Service
that started it, meaning that a running Task
will not prevent
the Service
from being garbage collected.
If an Executor
is specified on the Service
,
then it will be used to actually execute the service. Otherwise,
a daemon thread will be created and executed. If you wish to create
non-daemon threads, then specify a custom Executor
(for example,
you could use a ThreadPoolExecutor
with a custom
ThreadFactory
).
Because a Service
is intended to simplify declarative use cases, subclasses
should expose as properties the input parameters to the work to be done.
For example, to write a Service
that reads the first line
from any URL and returns it as a String
, it might be defined with
a single property, url
, and might be implemented as:
public static class FirstLineService extends Service<String> {
private StringProperty url = new SimpleStringProperty(this, "url");
public final void setUrl(String value) { url.set(value); }
public final String getUrl() { return url.get(); }
public final StringProperty urlProperty() { return url; }
protected Task createTask() {
final String _url = getUrl();
return new Task<String>() {
protected String call() throws Exception {
URL u = new URL(_url);
BufferedReader in = new BufferedReader(
new InputStreamReader(u.openStream()));
String result = in.readLine();
in.close();
return result;
}
};
}
}
The Service
by default uses a ThreadPoolExecutor
with some unspecified
default or maximum thread pool size. This is done so that naive code
will not completely swamp the system by creating thousands of Threads.
- Since:
- JavaFX 2.0
-
Property Summary
TypePropertyDescriptionfinal ReadOnlyObjectProperty
<Throwable> Gets the ReadOnlyObjectProperty representing any exception which occurred.final ObjectProperty
<Executor> The executor to use for running this Service.final ReadOnlyStringProperty
Gets the ReadOnlyStringProperty representing the message.The onCancelled event handler is called whenever the Task state transitions to the CANCELLED state.The onFailed event handler is called whenever the Task state transitions to the FAILED state.The onReady event handler is called whenever the Task state transitions to the READY state.The onRunning event handler is called whenever the Task state transitions to the RUNNING state.The onSchedule event handler is called whenever the Task state transitions to the SCHEDULED state.The onSucceeded event handler is called whenever the Task state transitions to the SUCCEEDED state.final ReadOnlyDoubleProperty
Gets the ReadOnlyDoubleProperty representing the progress.final ReadOnlyBooleanProperty
Gets the ReadOnlyBooleanProperty representing whether the Worker is running.Gets the ReadOnlyObjectProperty representing the current state.final ReadOnlyStringProperty
Gets the ReadOnlyStringProperty representing the title.final ReadOnlyDoubleProperty
Gets the ReadOnlyDoubleProperty representing the maximum amount of work that needs to be done.final ReadOnlyObjectProperty
<V> Gets the ReadOnlyObjectProperty representing the value.final ReadOnlyDoubleProperty
Gets the ReadOnlyDoubleProperty representing the current progress. -
Nested Class Summary
Nested classes/interfaces declared in interface javafx.concurrent.Worker
Worker.State
-
Constructor Summary
-
Method Summary
Modifier and TypeMethodDescriptionfinal <T extends Event>
voidaddEventFilter
(EventType<T> eventType, EventHandler<? super T> eventFilter) Registers an event filter for this target.final <T extends Event>
voidaddEventHandler
(EventType<T> eventType, EventHandler<? super T> eventHandler) Registers an event handler for this target.Construct an event dispatch chain for this target.boolean
cancel()
Cancels any currently running Task, if any.protected void
A protected convenience method for subclasses, called whenever the state of the Service has transitioned to the CANCELLED state.Invoked after the Service is started on the JavaFX Application Thread.final ReadOnlyObjectProperty
<Throwable> Gets the ReadOnlyObjectProperty representing any exception which occurred.protected void
executeTask
(Task<V> task) Uses theexecutor
defined on this Service to execute the given task.final ObjectProperty
<Executor> The executor to use for running this Service.protected void
failed()
A protected convenience method for subclasses, called whenever the state of the Service has transitioned to the FAILED state.protected final void
Fires the specified event.final Throwable
Gets the value of theexception
property.final Executor
Gets the value of theexecutor
property.final String
Gets the value of themessage
property.final EventHandler
<WorkerStateEvent> The onCancelled event handler is called whenever the Task state transitions to the CANCELLED state.final EventHandler
<WorkerStateEvent> The onFailed event handler is called whenever the Task state transitions to the FAILED state.final EventHandler
<WorkerStateEvent> The onReady event handler is called whenever the Task state transitions to the READY state.final EventHandler
<WorkerStateEvent> The onRunning event handler is called whenever the Task state transitions to the RUNNING state.final EventHandler
<WorkerStateEvent> The onSchedule event handler is called whenever the Task state transitions to the SCHEDULED state.final EventHandler
<WorkerStateEvent> The onSucceeded event handler is called whenever the Task state transitions to the SUCCEEDED state.final double
Gets the value of theprogress
property.final Worker.State
getState()
Gets the value of thestate
property.final String
getTitle()
Gets the value of thetitle
property.final double
Gets the value of thetotalWork
property.final V
getValue()
Gets the value of thevalue
property.final double
Gets the value of theworkDone
property.final boolean
Gets the value of therunning
property.final ReadOnlyStringProperty
Gets the ReadOnlyStringProperty representing the message.The onCancelled event handler is called whenever the Task state transitions to the CANCELLED state.The onFailed event handler is called whenever the Task state transitions to the FAILED state.The onReady event handler is called whenever the Task state transitions to the READY state.The onRunning event handler is called whenever the Task state transitions to the RUNNING state.The onSchedule event handler is called whenever the Task state transitions to the SCHEDULED state.The onSucceeded event handler is called whenever the Task state transitions to the SUCCEEDED state.final ReadOnlyDoubleProperty
Gets the ReadOnlyDoubleProperty representing the progress.protected void
ready()
A protected convenience method for subclasses, called whenever the state of the Service has transitioned to the READY state.final <T extends Event>
voidremoveEventFilter
(EventType<T> eventType, EventHandler<? super T> eventFilter) Unregisters a previously registered event filter from this target.final <T extends Event>
voidremoveEventHandler
(EventType<T> eventType, EventHandler<? super T> eventHandler) Unregisters a previously registered event handler from this target.void
reset()
Resets the Service.void
restart()
Cancels any currently running Task, if any, and restarts this Service.protected void
running()
A protected convenience method for subclasses, called whenever the state of the Service has transitioned to the RUNNING state.final ReadOnlyBooleanProperty
Gets the ReadOnlyBooleanProperty representing whether the Worker is running.protected void
A protected convenience method for subclasses, called whenever the state of the Service has transitioned to the SCHEDULED state.protected final <T extends Event>
voidsetEventHandler
(EventType<T> eventType, EventHandler<? super T> eventHandler) Sets the handler to use for this event type.final void
setExecutor
(Executor value) Sets the value of theexecutor
property.final void
The onCancelled event handler is called whenever the Task state transitions to the CANCELLED state.final void
setOnFailed
(EventHandler<WorkerStateEvent> value) The onFailed event handler is called whenever the Task state transitions to the FAILED state.final void
setOnReady
(EventHandler<WorkerStateEvent> value) The onReady event handler is called whenever the Task state transitions to the READY state.final void
setOnRunning
(EventHandler<WorkerStateEvent> value) The onRunning event handler is called whenever the Task state transitions to the RUNNING state.final void
The onSchedule event handler is called whenever the Task state transitions to the SCHEDULED state.final void
The onSucceeded event handler is called whenever the Task state transitions to the SUCCEEDED state.void
start()
Starts this Service.Gets the ReadOnlyObjectProperty representing the current state.protected void
A protected convenience method for subclasses, called whenever the state of the Service has transitioned to the SUCCEEDED state.final ReadOnlyStringProperty
Gets the ReadOnlyStringProperty representing the title.final ReadOnlyDoubleProperty
Gets the ReadOnlyDoubleProperty representing the maximum amount of work that needs to be done.final ReadOnlyObjectProperty
<V> Gets the ReadOnlyObjectProperty representing the value.final ReadOnlyDoubleProperty
Gets the ReadOnlyDoubleProperty representing the current progress.
-
Property Details
-
state
- Specified by:
stateProperty
in interfaceWorker<V>
- Returns:
- The property representing the state
- See Also:
-
value
- Specified by:
valueProperty
in interfaceWorker<V>
- Returns:
- The property representing the current value
- See Also:
-
exception
- Specified by:
exceptionProperty
in interfaceWorker<V>
- Returns:
- the property representing the exception
- See Also:
-
workDone
- Specified by:
workDoneProperty
in interfaceWorker<V>
- Returns:
- The property representing the amount of work done
- See Also:
-
totalWork
- Specified by:
totalWorkProperty
in interfaceWorker<V>
- Returns:
- the property representing the total work to be done
- See Also:
-
progress
- Specified by:
progressProperty
in interfaceWorker<V>
- Returns:
- the property representing the progress
- See Also:
-
running
- Specified by:
runningProperty
in interfaceWorker<V>
- Returns:
- the property representing whether the worker is running
- See Also:
-
message
- Specified by:
messageProperty
in interfaceWorker<V>
- Returns:
- a property representing the current message
- See Also:
-
title
- Specified by:
titleProperty
in interfaceWorker<V>
- Returns:
- the property representing the current title
- See Also:
-
executor
The executor to use for running this Service. If no executor is specified, then a new daemon thread will be created and used for running the Service using some default executor.- See Also:
-
onReady
The onReady event handler is called whenever the Task state transitions to the READY state.- Since:
- JavaFX 2.1
- See Also:
-
onScheduled
The onSchedule event handler is called whenever the Task state transitions to the SCHEDULED state.- Since:
- JavaFX 2.1
- See Also:
-
onRunning
The onRunning event handler is called whenever the Task state transitions to the RUNNING state.- Since:
- JavaFX 2.1
- See Also:
-
onSucceeded
The onSucceeded event handler is called whenever the Task state transitions to the SUCCEEDED state.- Since:
- JavaFX 2.1
- See Also:
-
onCancelled
The onCancelled event handler is called whenever the Task state transitions to the CANCELLED state.- Since:
- JavaFX 2.1
- See Also:
-
onFailed
The onFailed event handler is called whenever the Task state transitions to the FAILED state.- Since:
- JavaFX 2.1
- See Also:
-
-
Constructor Details
-
Service
protected Service()Create a new Service.
-
-
Method Details
-
getState
Gets the value of thestate
property. -
stateProperty
Description copied from interface:Worker
Gets the ReadOnlyObjectProperty representing the current state.- Specified by:
stateProperty
in interfaceWorker<V>
- Returns:
- the
state
property - See Also:
-
getValue
Gets the value of thevalue
property. -
valueProperty
Description copied from interface:Worker
Gets the ReadOnlyObjectProperty representing the value.- Specified by:
valueProperty
in interfaceWorker<V>
- Returns:
- the
value
property - See Also:
-
getException
Gets the value of theexception
property.- Specified by:
getException
in interfaceWorker<V>
- Property description:
- Returns:
- the value of the
exception
property - See Also:
-
exceptionProperty
Description copied from interface:Worker
Gets the ReadOnlyObjectProperty representing any exception which occurred.- Specified by:
exceptionProperty
in interfaceWorker<V>
- Returns:
- the
exception
property - See Also:
-
getWorkDone
public final double getWorkDone()Gets the value of theworkDone
property.- Specified by:
getWorkDone
in interfaceWorker<V>
- Property description:
- Returns:
- the value of the
workDone
property - See Also:
-
workDoneProperty
Description copied from interface:Worker
Gets the ReadOnlyDoubleProperty representing the current progress.- Specified by:
workDoneProperty
in interfaceWorker<V>
- Returns:
- the
workDone
property - See Also:
-
getTotalWork
public final double getTotalWork()Gets the value of thetotalWork
property.- Specified by:
getTotalWork
in interfaceWorker<V>
- Property description:
- Returns:
- the value of the
totalWork
property - See Also:
-
totalWorkProperty
Description copied from interface:Worker
Gets the ReadOnlyDoubleProperty representing the maximum amount of work that needs to be done. These "work units" have meaning to the Worker implementation, such as the number of bytes that need to be downloaded or the number of images to process or some other such metric.- Specified by:
totalWorkProperty
in interfaceWorker<V>
- Returns:
- the
totalWork
property - See Also:
-
getProgress
public final double getProgress()Gets the value of theprogress
property.- Specified by:
getProgress
in interfaceWorker<V>
- Property description:
- Returns:
- the value of the
progress
property - See Also:
-
progressProperty
Description copied from interface:Worker
Gets the ReadOnlyDoubleProperty representing the progress.- Specified by:
progressProperty
in interfaceWorker<V>
- Returns:
- the
progress
property - See Also:
-
isRunning
public final boolean isRunning()Gets the value of therunning
property. -
runningProperty
Description copied from interface:Worker
Gets the ReadOnlyBooleanProperty representing whether the Worker is running.- Specified by:
runningProperty
in interfaceWorker<V>
- Returns:
- the
running
property - See Also:
-
getMessage
Gets the value of themessage
property.- Specified by:
getMessage
in interfaceWorker<V>
- Property description:
- Returns:
- the value of the
message
property - See Also:
-
messageProperty
Description copied from interface:Worker
Gets the ReadOnlyStringProperty representing the message.- Specified by:
messageProperty
in interfaceWorker<V>
- Returns:
- the
message
property - See Also:
-
getTitle
Gets the value of thetitle
property. -
titleProperty
Description copied from interface:Worker
Gets the ReadOnlyStringProperty representing the title.- Specified by:
titleProperty
in interfaceWorker<V>
- Returns:
- the
title
property - See Also:
-
setExecutor
Sets the value of theexecutor
property.- Property description:
- The executor to use for running this Service. If no executor is specified, then a new daemon thread will be created and used for running the Service using some default executor.
- Parameters:
value
- the value for theexecutor
property- See Also:
-
getExecutor
Gets the value of theexecutor
property.- Property description:
- The executor to use for running this Service. If no executor is specified, then a new daemon thread will be created and used for running the Service using some default executor.
- Returns:
- the value of the
executor
property - See Also:
-
executorProperty
The executor to use for running this Service. If no executor is specified, then a new daemon thread will be created and used for running the Service using some default executor.- Returns:
- the
executor
property - See Also:
-
onReadyProperty
The onReady event handler is called whenever the Task state transitions to the READY state.- Returns:
- the onReady event handler property
- Since:
- JavaFX 2.1
- See Also:
-
getOnReady
The onReady event handler is called whenever the Task state transitions to the READY state.- Returns:
- the onReady event handler, if any
- Since:
- JavaFX 2.1
-
setOnReady
The onReady event handler is called whenever the Task state transitions to the READY state.- Parameters:
value
- the event handler, can be null to clear it- Since:
- JavaFX 2.1
-
ready
protected void ready()A protected convenience method for subclasses, called whenever the state of the Service has transitioned to the READY state. This method is invoked after the Service has been fully transitioned to the new state.- Since:
- JavaFX 2.1
-
onScheduledProperty
The onSchedule event handler is called whenever the Task state transitions to the SCHEDULED state.- Returns:
- the onScheduled event handler property
- Since:
- JavaFX 2.1
- See Also:
-
getOnScheduled
The onSchedule event handler is called whenever the Task state transitions to the SCHEDULED state.- Returns:
- the onScheduled event handler, if any
- Since:
- JavaFX 2.1
-
setOnScheduled
The onSchedule event handler is called whenever the Task state transitions to the SCHEDULED state.- Parameters:
value
- the event handler, can be null to clear it- Since:
- JavaFX 2.1
-
scheduled
protected void scheduled()A protected convenience method for subclasses, called whenever the state of the Service has transitioned to the SCHEDULED state. This method is invoked after the Service has been fully transitioned to the new state.- Since:
- JavaFX 2.1
-
onRunningProperty
The onRunning event handler is called whenever the Task state transitions to the RUNNING state.- Returns:
- the onRunning event handler property
- Since:
- JavaFX 2.1
- See Also:
-
getOnRunning
The onRunning event handler is called whenever the Task state transitions to the RUNNING state.- Returns:
- the onRunning event handler, if any
- Since:
- JavaFX 2.1
-
setOnRunning
The onRunning event handler is called whenever the Task state transitions to the RUNNING state.- Parameters:
value
- the event handler, can be null to clear it- Since:
- JavaFX 2.1
-
running
protected void running()A protected convenience method for subclasses, called whenever the state of the Service has transitioned to the RUNNING state. This method is invoked after the Service has been fully transitioned to the new state.- Since:
- JavaFX 2.1
-
onSucceededProperty
The onSucceeded event handler is called whenever the Task state transitions to the SUCCEEDED state.- Returns:
- the onSucceeded event handler property
- Since:
- JavaFX 2.1
- See Also:
-
getOnSucceeded
The onSucceeded event handler is called whenever the Task state transitions to the SUCCEEDED state.- Returns:
- the onSucceeded event handler, if any
- Since:
- JavaFX 2.1
-
setOnSucceeded
The onSucceeded event handler is called whenever the Task state transitions to the SUCCEEDED state.- Parameters:
value
- the event handler, can be null to clear it- Since:
- JavaFX 2.1
-
succeeded
protected void succeeded()A protected convenience method for subclasses, called whenever the state of the Service has transitioned to the SUCCEEDED state. This method is invoked after the Service has been fully transitioned to the new state.- Since:
- JavaFX 2.1
-
onCancelledProperty
The onCancelled event handler is called whenever the Task state transitions to the CANCELLED state.- Returns:
- the onCancelled event handler property
- Since:
- JavaFX 2.1
- See Also:
-
getOnCancelled
The onCancelled event handler is called whenever the Task state transitions to the CANCELLED state.- Returns:
- the onCancelled event handler, if any
- Since:
- JavaFX 2.1
-
setOnCancelled
The onCancelled event handler is called whenever the Task state transitions to the CANCELLED state.- Parameters:
value
- the event handler, can be null to clear it- Since:
- JavaFX 2.1
-
cancelled
protected void cancelled()A protected convenience method for subclasses, called whenever the state of the Service has transitioned to the CANCELLED state. This method is invoked after the Service has been fully transitioned to the new state.- Since:
- JavaFX 2.1
-
onFailedProperty
The onFailed event handler is called whenever the Task state transitions to the FAILED state.- Returns:
- the onFailed event handler property
- Since:
- JavaFX 2.1
- See Also:
-
getOnFailed
The onFailed event handler is called whenever the Task state transitions to the FAILED state.- Returns:
- the onFailed event handler, if any
- Since:
- JavaFX 2.1
-
setOnFailed
The onFailed event handler is called whenever the Task state transitions to the FAILED state.- Parameters:
value
- the event handler, can be null to clear it- Since:
- JavaFX 2.1
-
failed
protected void failed()A protected convenience method for subclasses, called whenever the state of the Service has transitioned to the FAILED state. This method is invoked after the Service has been fully transitioned to the new state.- Since:
- JavaFX 2.1
-
cancel
public boolean cancel()Cancels any currently running Task, if any. The state will be set to CANCELLED. -
restart
public void restart()Cancels any currently running Task, if any, and restarts this Service. The state will be reset to READY prior to execution. This method should only be called on the FX application thread. -
reset
public void reset()Resets the Service. May only be called while in one of the finish states, that is, SUCCEEDED, FAILED, or CANCELLED, or when READY. This method should only be called on the FX application thread. -
start
public void start()Starts this Service. The Service must be in the READY state to succeed in this call. This method should only be called on the FX application thread. -
executeTask
Uses the
executor
defined on this Service to execute the given task. If theexecutor
is null, then a default executor is used which will create a new daemon thread on which to execute this task.This method is intended only to be called by the Service implementation.
- Parameters:
task
- a non-null task to execute- Since:
- JavaFX 2.1
-
addEventHandler
public final <T extends Event> void addEventHandler(EventType<T> eventType, EventHandler<? super T> eventHandler) Registers an event handler for this target.The handler is called when the target receives an
Event
of the specified type during the bubbling phase of event delivery.- Specified by:
addEventHandler
in interfaceEventTarget
- Type Parameters:
T
- the event class of the handler- Parameters:
eventType
- the type of the events received by the handlereventHandler
- the event handler- Since:
- JavaFX 2.1
-
removeEventHandler
public final <T extends Event> void removeEventHandler(EventType<T> eventType, EventHandler<? super T> eventHandler) Unregisters a previously registered event handler from this target.Since it is possible to register a single
EventHandler
instance for different event types, the caller needs to specify the event type from which the handler should be unregistered.- Specified by:
removeEventHandler
in interfaceEventTarget
- Type Parameters:
T
- the event class of the handler- Parameters:
eventType
- the event type from which to unregistereventHandler
- the event handler- Since:
- JavaFX 2.1
-
addEventFilter
public final <T extends Event> void addEventFilter(EventType<T> eventType, EventHandler<? super T> eventFilter) Registers an event filter for this target.The filter is called when the target receives an
Event
of the specified type during the capturing phase of event delivery.- Specified by:
addEventFilter
in interfaceEventTarget
- Type Parameters:
T
- the event class of the filter- Parameters:
eventType
- the type of the events received by the filtereventFilter
- the event filter- Since:
- JavaFX 2.1
-
removeEventFilter
public final <T extends Event> void removeEventFilter(EventType<T> eventType, EventHandler<? super T> eventFilter) Unregisters a previously registered event filter from this target.Since it is possible to register a single
EventHandler
instance for different event types, the caller needs to specify the event type from which the filter should be unregistered.- Specified by:
removeEventFilter
in interfaceEventTarget
- Type Parameters:
T
- the event class of the filter- Parameters:
eventType
- the event type from which to unregistereventFilter
- the event filter- Since:
- JavaFX 2.1
-
setEventHandler
protected final <T extends Event> void setEventHandler(EventType<T> eventType, EventHandler<? super T> eventHandler) Sets the handler to use for this event type. There can only be one such handler specified at a time. This handler is guaranteed to be called first. This is used for registering the user-defined onFoo event handlers.- Type Parameters:
T
- the specific event class of the handler- Parameters:
eventType
- the event type to associate with the given eventHandlereventHandler
- the handler to register, or null to unregister- Throws:
NullPointerException
- if the event type is null- Since:
- JavaFX 2.1
-
fireEvent
Fires the specified event. Any event filter encountered will be notified and can consume the event. If not consumed by the filters, the event handlers on this task are notified. If these don't consume the event either, then all event handlers are called and can consume the event.This method must be called on the FX user thread.
- Parameters:
event
- the event to fire- Since:
- JavaFX 2.1
-
buildEventDispatchChain
Description copied from interface:EventTarget
Construct an event dispatch chain for this target. The event dispatch chain contains event dispatchers which might be interested in processing of events targeted at thisEventTarget
. This event target is not automatically added to the chain, so if it wants to process events, it needs to add anEventDispatcher
for itself to the chain.In the case the event target is part of some hierarchy, the chain for it is usually built from event dispatchers collected from the root of the hierarchy to the event target.
The event dispatch chain is constructed by modifications to the provided initial event dispatch chain. The returned chain should have the initial chain at its end so the dispatchers should be prepended to the initial chain.
The caller shouldn't assume that the initial chain remains unchanged nor that the returned value will reference a different chain.
- Specified by:
buildEventDispatchChain
in interfaceEventTarget
- Parameters:
tail
- the initial chain to build from- Returns:
- the resulting event dispatch chain for this target
-
createTask
Invoked after the Service is started on the JavaFX Application Thread. Implementations should save off any state into final variables prior to creating the Task, since accessing properties defined on the Service within the background thread code of the Task will result in exceptions. For example:protected Task createTask() { final String url = myService.getUrl(); return new Task<String>() { protected String call() { URL u = new URL("http://www.oracle.com"); BufferedReader in = new BufferedReader( new InputStreamReader(u.openStream())); String result = in.readLine(); in.close(); return result; } } }
If the Task is a pre-defined class (as opposed to being an anonymous class), and if it followed the recommended best-practice, then there is no need to save off state prior to constructing the Task since its state is completely provided in its constructor.
protected Task createTask() { // This is safe because getUrl is called on the FX Application // Thread and the FirstLineReaderTasks stores it as an // immutable property return new FirstLineReaderTask(myService.getUrl()); }
- Returns:
- the Task to execute
-