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Timer problems with swing GUI components

This snippet of code essentially reveals the back side of the cards when clicked. The showFace function sets the icon and text and therefore implying the front of the card. Light gray background is the back. If a non matching card is clicked, I first intend to showFace for a brief moment ( 2 seconds) than revert to the "back side of the card." However, upon clicking a non matching card, the icon and text flashes instantaneously and reverts to its gray background.
Tried changing the 2000 milliseconds to something higher but no avail. Any help is appreciated.
else if (currentMode == 1){
//matched cards
if(checkCards(currentCard, names)){
showFace();
currentMode = 0;
currentCard = "";
deafTo(this);
}
//else non match, still checking mode
else{
showFace();
var timer: Timer = null;
val action = new ActionListener(){
override def actionPerformed(event : ActionEvent){
icon = null;
text = "";
background = Color.DARK_GRAY;
timer.stop();
}
};
timer = new Timer (2000, action);
timer.setInitialDelay(0);
timer.start();
}
}
def showFace()={
text = names;
horizontalTextPosition = Alignment.Center;
verticalTextPosition = Alignment.Bottom;
background = Color.WHITE;
val icons = new ImageIcon(path);
val newIc = icons.getImage();
val newIcons = newIc.getScaledInstance(100, 75,
java.awt.Image.SCALE_SMOOTH);
icon = new ImageIcon(newIcons);
repaint();
}

This is because you set an initial delay of 2000ms in the constructor
timer = new Timer(2000, action)
But then you overwrite it to 0ms by:
timer.setInitialDelay(0);
Remove this line and you should be good.
You can check here Swing Timer API.
And see some examples here.

Javadoc http://docs.oracle.com/javase/7/docs/api/java/util/Timer.html
This class does not offer real-time guarantees: it schedules tasks using the Object.wait(long) method.
Java 5.0 introduced the java.util.concurrent package and one of the concurrency utilities therein is the ScheduledThreadPoolExecutor which is a thread pool for repeatedly executing tasks at a given rate or delay. It is effectively a more versatile replacement for the Timer/TimerTask combination, as it allows multiple service threads, accepts various time units, and doesn't require subclassing TimerTask (just implement Runnable). Configuring ScheduledThreadPoolExecutor with one thread makes it equivalent to Timer.

Refreshing JTable step by step in Java

I am doing a Pacman game using A* algorithm in Java. I searched a lot of questions. I found a solution for one step. But I want to refresh my table in while block and my solution is just refreshing JTable according to the last step(just showing the result) in while(calculated all steps). But I want to refresh and show Pacman's places(location) step by step in while block. It has to look like Pacmans are moving. But I couldn't. My codes is below:
btnStartGame.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent arg0) {
//randomly placement of Pacmans
table_1.setValueAt(yellowPacman, locationyellowX, locationyellowY);
...calculating heuristics
//after calculation
newXYellow =locationyellowX;
newYYellow =locationyellowY+1;
nodeYellow = 10 * newXYellow + newYYellow;
while(heuristics != zero){
...enemy pacmans' movement
//after enemy pacmans' movement calculating yellow pacman's movement
if((newXYellow>=0 && newXYellow<10 && newYYellow>=0 && newYYellow<10) && !wallList.contains(nodeYellow)){
//calculate heuristic again
manhattanDistance[0][0] = Math.abs(newXYellow-locationblackX[0])+
Math.abs(newYYellow-locationblackX[0]);
manhattanDistance[0][1] = Math.abs(newXYellow-locationblackX[1])+
Math.abs(newYYellow-locationblackX[1]);
manhattanDistance[0][2] = Math.abs(newXYellow-locationblackX[2])+
Math.abs(newYYellow-locationblackX[2]);
fyellow[0] = manhattanDistance[0][0] + manhattanDistance[0][1] + manhattanDistance[0][2];
selectedNodeXYellow = newXYellow;
selectedNodeYYellow = newYYellow;
timer2.start();//updated
while(delay != 0)
delay--;
delay = 4000;
locationyellowX = selectedNodeXYellow;
locationyellowY = selectedNodeYYellow;
nodeYellow = 10 * selectedNodeXYellow+ selectedNodeYYellow;
timer3.start();//updated
while(delay != 0)
delay--;
delay = 10000;
}//ending if
}//ending while
}
}//ending action
timer2 = new Timer(ONE_SECOND, new ActionListener() {
public void actionPerformed(ActionEvent evt) {
table_1.setValueAt(null, locationyellowX, locationyellowY);//I wanted to delete old moves
timer2.stop();
}
});
timer3 = new Timer(ONE_SECOND, new ActionListener() {
public void actionPerformed(ActionEvent evt) {
table_1.setValueAt(yellowIcon, locationyellowX, locationyellowY);//here I want to show each moves step by step in while block
timer3.stop();
}
});
UPDATE 1 :
Delay was just an idea. Maybe algorithm is calculated too quickly and timers cannot be fired. But it didn't work and also does not timer suppose to be fired at each one second? still I've seen the last values of JTable.

I suspect your main issue here is that you need to understand how the various threads in a Java GUI application work. Specifically, if you have code executing in the event dispatch thread then there will be no updates to the UI while that code is executing. In your case you are making multiple updates to a JTable and then returning control to the display which will then show the last value.
The solution here is to introduce a timer element that executes each step of your algorithm in each tick of the timer and then returns control to display the result. Check the javax.swing.Timer class for details. I also suggest you read the sections 'concurrency in Swing' and 'How to use Swing Timers' in the Java tutorials.

when shooting constantly repeats and goes faster every key stroke

Ok so i'm going to try to explain this, well I created a shoot method in a class that contains my bluespell, and all of it's constructors, well the problem is when I press space once it constantly shoots without me pressing it again, and if I press it twice the speed at which it fires doubles and it starts to contain more than one x and y position on my grid I just want the spell to fire when fired and I only need one item because I don't want there to be more than one instance of it on the grid I want it to be that the player cannot fire until the spell has left the grid, here's my code thanks oh and I only have it called in my key released seeing as it should only do it once the key has been released, but if that should change please let me know thanks :)
public void shootSpell(){
final BlueSpell b = new BlueSpell(GoodGuy.getx(), GoodGuy.gety() +1, BlueSpellWizard());
int delay = 100;
ActionListener taskPerformed = new ActionListener(){
public void actionPerformed(ActionEvent e){
if(b.gety() != 19){
WizardCells[b.getx()][b.gety()].setIcon(null);
WizardCells[b.getx()][b.changey(b.gety()+1)].setIcon(b.getIcon());
}
else{
WizardCells[b.getx()][b.gety()].setIcon(null);
b.changex(GoodGuy.getx());
b.changey(GoodGuy.gety() +1);
}
}
};
new Timer(delay, taskPerformed).start();
else if(key == KeyEvent.VK_SPACE){
GoodSpell.shootSpell();
}

Do not use a Timer! Your task should not repeat every 100 milliseconds. If I understand your code, you should run the code from your ActionListener in a new thread.
// Something like this,
new Thread(new Runnable() {
public void run() {
if (b.gety() != 19) {
WizardCells[b.getx()][b.gety()].setIcon(null);
WizardCells[b.getx()][b.changey(b.gety() + 1)].setIcon(b
.getIcon());
} else {
WizardCells[b.getx()][b.gety()].setIcon(null);
b.changex(GoodGuy.getx());
b.changey(GoodGuy.gety() + 1);
}
}
}).start();

You also need to do a check if the spell is currently in view/activate prior to initiating a new spell in the shoot() method...
public void shootSpell(){
//do a check here if a spell is already running!
final BlueSpell b = new BlueSpell(GoodGuy.getx(), GoodGuy.gety() +1, BlueSpellWizard());
int delay = 100;
//......
So in your method that is updating the spell going accross the screen you either need to have a flag in there if its still active, or if you are running it in a new thread, save that thread to a global var and check to see if the thread is running prior instantiating a new BlueSpell()

Making moving motion with labels using threads in java

I'm having a problem I'm making a pool game and I need the ballos to react when I simulate a hit, the program works like this, you click the direction and power to hit the ball and the click go, the go button is in the GUI class where my labels are created, the button calls a method from my main class that recieves the parameter and then with a while in it, changes the X and Y of the ball till the power is reduced to 0 and then stops, the code is working, but the ball moves until the while stops. So the while works and when the power int is 0 the while goes out and then the new X,Y are painted.
This is the funcion that the button calls, the button sends all the parameters
public void golpe(int pbola, int pvelocidad, String pdireccion, JLabel[] listalabels) throws InterruptedException{
listabolas[pbola].setVelocidad(pvelocidad);
listabolas[pbola].setDireccion(pdireccion);
while (listabolas[pbola].getVelocidad() > 0) {
moverBola(pbola, listalabels);
//System.out.println(listabolas[pbola].getPosX());
//System.out.println(listabolas[pbola].getPosY());
Thread.sleep(500);
//This line is supposed to change the X and Y of the object over and over
//but only does it till the end
listalabels[pbola].setLocation(listabolas[pbola].getPosX(), listabolas[pbola].getPosY());
}
}
Here is the function moverbola(), only copied one "if" so that the code doesn't look to big
private void moverBola(int pbola, JLabel[] listalabels) {
if (listabolas[pbola].getDireccion().equals("SE")) {
int pposX = listabolas[pbola].getPosX();
listabolas[pbola].setPosX(pposX + 1);
int pposY = listabolas[pbola].getPosY();
listabolas[pbola].setPosY(pposY + 1);
}

Swing is a single threaded framework. That is, all interactions with UI are expected to occur from within a single thread, known as the Event Dispatching Thread.
Any action that blocks this thread, will prevent the EDT from updating the screen or processing any new events.
Your while-loop is blocking the EDT, preventing it from painting any updates until after the while-loop is completed.
Take a look at Concurrency in Swing for more details.
There are a number of approaches you could take...
You could use a Thread, but this causes problems as you need to ensure that any changes you make to the UI are re-synced back to the EDT and this can become messy...
For example
You could use a javax.swing.Timer that ticks at a regular interval and you would update any internal parameters from within it's assigned ActionListener. Because the tick events occur within the EDT, it is save to update the screen from within it.
For example
You could use a SwingWorker to run the task in the background. It has methods for re-syncing updates back to the EDT, but might be a little over kill for your purposes...
Updated with a possible Timer example
Caveat- It is very hard to produce a reasonable example with only a code snippet, but, something like this might work
public void golpe(final int pbola, int pvelocidad, String pdireccion, final JLabel[] listalabels) throws InterruptedException{
listabolas[pbola].setVelocidad(pvelocidad);
listabolas[pbola].setDireccion(pdireccion);
Timer timer = new Timer(40, new ActionListener() {
public void actionPerformed(ActionEvent evt) {
if (listabolas[pbola].getVelocidad() == 0) {
((Timer)evt.getSource()).stop();
} else {
moverBola(pbola, listalabels);
}
}
});
timer.setRepeats(true);
timer.start();
}

Change focused button every x seconds in java

I'm looking for the best way to do the following. If someone could point me in the right direction I'd be greatfull.
I have 5 buttons,
Button 1
Button 2
Button 3
Button 4
Button 5
What I'd like to happen is every 5 seconds the focus of the button move one down. So the app starts and Button 1 has focus. Then 5 seconds later button 2 takes focus and so on so on until Button 5 and then back to Button 1. When I say focus I mean that if the space bar was pressed the button would be pressed. Any assistance would be appreciated. Thanks

You could use a java swing timer for this task. Take a look at the example in oracle docs
http://docs.oracle.com/javase/tutorial/uiswing/misc/timer.html

You can use the KeyboardFocusManager for this as well. Sample code below using Timer object from java.util. The code below changes focus every 500 ms.
final KeyboardFocusManager manager = KeyboardFocusManager.getCurrentKeyboardFocusManager();
Timer timer = new Timer();
timer.scheduleAtFixedRate(new TimerTask() {
public void run() {
manager.focusNextComponent();
}
}, 0, 500);
Hope this helps.

You can create thread that sleeps for 5 senconds, then awakes and sets focus to the next button. Store your buttons in array.
final int n = 5;
final int TIMEOUT = 5000;
Button[] buttons = new Button[n];
// fill the array
new Thread() {
for (i = 0; ; i < n ? i++ : i = 0) {
buttons.requestFocusInWindow();
try {
Thread.sleep(TIMEOUT);
} catch(InterruptedException e) {}
}
}.start();
You can also use java.util.Timer