Javafx: Automatic update of table cell using Thread - multithreading

Question

I have a Trade class which contains a property currentPrice, which downloads price data from a website using getPricedata() method. The Trade object will show up as a table row in TableView. Now, my task: is to
use the getPricedata() method to grab data from internet, populate the currentPrice cell, whenever the object is created.
relaunch the getPricedata() method to every 1 minute after the object has been created and update table cell.
Below is the basic structure of my code. But I have no idea how to implement this ?
Which package do I need ? Task ? Service ? ScheduledService ?
public class Trade{
private DoubleProperty currentPrice;
// need thread here
public double getPricedata(){
.......
}
}

Answer 1

Use a ScheduledService<Number>, whose Task<Number>'s call() method retrieves and returns the value. Then you can either register an onSucceeded handler with the service, or just bind the Trade's currentPrice to service.lastValue(). Call setPeriod(..) on the service (once) to configure it to run every minute.
Since the currentPrice is being set from the service, you should only expose a ReadOnlyDoubleProperty from your Trade class (otherwise you might try to call currentPriceProperty().set(...) or setCurrentPrice(...), which would fail as it's bound).
I would do something like
public class Trade {
private final ReadOnlyDoubleWrapper currentPrice ;
private final ScheduledService<Number> priceService = new ScheduledService<Number>() {
#Override
public Task<Number> createTask() {
return new Task<Number>() {
#Override
public Number call() {
return getPriceData();
}
};
}
};
public Trade() {
priceService.setPeriod(Duration.minutes(1));
// in case of errors running service:
priceService.setOnFailed(e -> priceService.getException().printStackTrace());
currentPrice = new ReadOnlyDoubleWrapper(0);
currentPrice.bind(priceService.lastValueProperty());
startMonitoring();
}
public final void startMonitoring() {
priceService.restart();
}
public final void stopMonitoring() {
priceService.cancel();
}
public ReadOnlyDoubleProperty currentPriceProperty() {
return currentPrice.getReadOnlyProperty();
}
public final double getCurrentPrice() {
return currentPriceProperty().get();
}
private double getPriceData() {
// do actual retrieval work here...
}
}
(Code just typed in here without testing, but it should give you the idea.)