SwingWorker's @Override process() error ?

Folks,

I'm stumped... I'm trying to get "interim results from the worker thread" (Flipper.java) working from the [url=http://java.sun.com/docs/books/tutorial/uiswing/concurrency/interim.html]Swing Tutorial[/url]/

I get this compiler error:Flipper.java:89: method does not override or implement a method from a supertype

... This is line 89 & 90 of Flipper.java ....

@Override

protectedvoid process(List<FlipPair> pairs){

but the [url=http://java.sun.com/javase/6/docs/api/javax/swing/SwingWorker.html]SwingWorker javadoc[/url] says:protectedvoid process(List<V> chunks);

// Receives data chunks from the publish method asynchronously on the Event Dispatch Thread.

The whole application isFlipper.java:import java.util.List;

import java.util.Random;

import java.awt.event.ActionListener;

import java.awt.event.ActionEvent;

import java.awt.GridBagLayout;

import java.awt.GridBagConstraints;

import java.awt.Insets;

import javax.swing.JButton;

import javax.swing.JFrame;

import javax.swing.JTextField;

import javax.swing.SwingUtilities;

import javax.swing.border.Border;

import javax.swing.BorderFactory;

import javax.swing.SwingWorker;

publicclass Flipperextends JFrameimplements ActionListener{

publicstaticfinallong serialVersionUID = 79843532;

privatefinal GridBagConstraints constraints;

privatefinal JTextField headsText, totalText, devText;

privatefinal Border border = BorderFactory.createLoweredBevelBorder();

privatefinal JButton startButton, stopButton;

private FlipTask flipTask;

private JTextField makeText(){

JTextField t =new JTextField(20);

t.setEditable(false);

t.setHorizontalAlignment(JTextField.RIGHT);

t.setBorder(border);

getContentPane().add(t, constraints);

return t;

}

private JButton makeButton(String caption){

JButton b =new JButton(caption);

b.setActionCommand(caption);

b.addActionListener(this);

getContentPane().add(b, constraints);

return b;

}

public Flipper(){

super("Flipper");

setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

//Make text boxes

getContentPane().setLayout(new GridBagLayout());

constraints =new GridBagConstraints();

constraints.insets =new Insets(3, 10, 3, 10);

headsText = makeText();

totalText = makeText();

devText = makeText();

//Make buttons

startButton = makeButton("Start");

stopButton = makeButton("Stop");

stopButton.setEnabled(false);

//Display the window.

pack();

setVisible(true);

}

privatestaticclass FlipPair{

privatefinallong heads, total;

FlipPair(long heads,long total){

this.heads = heads;

this.total = total;

}

privateclass FlipTaskextends SwingWorker<Void, FlipPair>{

@Override

protected Void doInBackground(){

System.out.println("DEBUG: doInBackground");

long heads = 0;

long total = 0;

Random random =new Random();

while (!isCancelled()){

try{ Thread.sleep(random.nextInt(50));}catch (InterruptedException ignore){}

total++;

if (random.nextBoolean()){

heads++;

}

publish(new FlipPair(heads, total));

//System.out.println("DEBUG: FlipTask main loop");

}

returnnull;

}

@Override

protectedvoid process(List<FlipPair> pairs){

System.out.println("DEBUG: process");

FlipPair pair = pairs.get(pairs.size() - 1);

headsText.setText(String.format("%d", pair.heads));

totalText.setText(String.format("%d", pair.total));

double bias = ((double) pair.heads) / ((double) pair.total) - 0.5;

devText.setText(String.format("%.10g", bias));

}

publicvoid actionPerformed(ActionEvent e){

if ("Start".equals(e.getActionCommand())){

startButton.setEnabled(false);

stopButton.setEnabled(true);

(flipTask =new FlipTask()).execute();

}elseif ("Stop".equals(e.getActionCommand())){

startButton.setEnabled(true);

stopButton.setEnabled(false);

flipTask.cancel(true);

flipTask =null;

}

publicstaticvoid main(String[] args){

SwingUtilities.invokeLater(

new Runnable(){

publicvoid run(){

new Flipper();

}

);

}

I tried just commenting out the @Override... and it compiles OK but I don't see the "DEBUG: process" message... I've tried it with and without the Thread.sleep (?which I suspect is "bad" in a Swing app?)

It looks like the main GUI event thread is blocked, but by what?

Please, any assistance would be appreciated.

Keith.

corlettk: oooops I just realised this question belongs on the SWING FORUM, so I'm going to cross post it there... Sorry. Flame me!

Oh, and I'm using java version "1.6.0-beta2" on an AMD dual core 64 running XP.

[9726 byte] By [corlettka] at [2007-11-26 17:14:50]

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SwingWorker's @Override process() error ?

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