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How can I stop a Swing Timer after n seconds?

I'm trying to make an image twinkle with RaffleImage(); while I'm executing the timer, my character is immune to any collision, I want it to be immune only for 2 seconds, so the timer get execute only for 2 seconds and then get finished.
I've tried subtracting System.currentTimeMillis() but any variable I create from this method, have always the same value, making me get a zero from that subtracting.
Do you know how I can stop or pause the timer after any elapsed time in seconds?
immuneTimer = new Timer(50, new ActionListener() {
#Override
public synchronized void actionPerformed(ActionEvent e) {
long initMillis = System.currentTimeMillis();
if (System.currentTimeMillis() - initMillis > 2000 ) { // this substract gives me 0
initImages();
setImmune(false); // so this never reached
immuneTimer.stop();
} else {
raffleImage(); //its executing like forever;
}
}
});

The Swing timer fires a an ActionEvent. From the event you can use getSource() to get the source of the event. Cast that source to the swing timer object and use that to turn it off.
To know when to turn it off you need to have a variable count the number of times the swing timer is invoked. When the variable reaches that amount, turn it off.
int elapsedTime = 0;
int timerDelay = 50;
int max = 2000;
public void actionPerformed(ActionEvent ae) {
elapsedTime += timerDelay; // you could use getDelay here but it
// is in milliseconds.
if (elapsedTime >= max) {
Timer s = (Timer)ae.getSource();
s.stop();
}
// rest of code
}

Progressively increase integer / increase int on regular interval

I just recently started playing around with Java/Android.
I am trying to make a very simple Android app. I want a number to be progressively increased. Something like:
int x = 0;
then every 0.1 seconds, x++. Then I can set the text of a textview
.setText(String.valueOf(x));
So in the program it will have an integer number increasing from 0 by 1 every 0.1 seconds.
Meanwhile all other functions/code should run normally while this is happening in the background

you could use the TextView's internal handler and its postDelayed method, to increment the int . E.g.
textView.postDelayed(new Runnable() {
#Override
public void run() {
textView.setText(String.valueOf(++x));
textView.postDelayed(this, 100);
}
}, 100);
where 100 is 100 milliseconds. Don't forget to call
textView.removeCallbacks(null);
when your activity is paused

you can use:
int x = 0;
TimerTask scanTask;
Timer t = new Timer();
public void incrementValue(){
scanTask = new TimerTask() {
public void run() {
x++;
}};
t.schedule(scanTask, 100, 100);
}
and use t.cancel(); whenever you want to stop the task.

How to get time left in a java.util.Timer?

How can I get the time left in a util.Timer?
What I want to do is to add a progressbar that displays time left until the timer starts over.
This is what I've got this far:
int seconds = 8;
java.util.Timer timer = new Timer();
timer.schedule( new TimerTask(){
public void run(){
// Do something
// Add a progressbar that displays time left until the timer "starts over".
},0,(long) (seconds*1000));

You would need a second timer to refresh the gui in a specific interval.
Another way to achieve this, would be to activate a single timer every second and update the counting in the ui. If the time is up, call your specific action.
A simple expample with console output only:
TimerTask task = new TimerTask()
{
int seconds = 8;
int i = 0;
#Override
public void run()
{
i++;
if(i % seconds == 0)
System.out.println("Timer action!");
else
System.out.println("Time left:" + (seconds - (i %seconds)) );
}
};
Timer timer = new Timer();
timer.schedule(task, 0, 1000);
It's output would be:
Time left:7
Time left:6
Time left:5
Time left:4
Time left:3
Time left:2
Time left:1
Timer action!
Time left:7
Time left:6
Time left:5
Time left:4
Time left:3
Time left:2
Time left:1
Timer action!
Time left:7
Time left:6
...
Then simply change the System.out's with your code to update the progress bar. Remember: java.util.Timer starts its own Thread. Swing is not thread safe, so you need to put every gui changing code into SwingUtilities.invokeLater()!
If you're not doing any long running tasks, every time your timer reachs the 8 seconds mark, you may want to use javax.swing.Timer directly. It uses the EDT and not its own Thread, so you don't need to synchronize your calls to Swing components with SwingUtilities.invokeLater().
Also see:
javax.swing.Timer vs java.util.Timer inside of a Swing application

All you need to do is declare a long variable timeleft in your MainActivity.
long timeleft;
Then, when you create a new Timer, set the "onTick" override to update the timeleft variable each "onTick" (which in the following example is 1000 milliseconds )
timer = new CountDownTimer(time, 1000) {
#Override
public void onTick(long millisecondsUntilFinished) {
timeleft = millisecondsUntilFinished;
}
}
Your app can access then the variable timeleft every time you need to check how much time is left.

how to stop a timer with 'if'

hi guys i am new to java... :(
i just want my button(start) to start a timer but i want to stop the timer automatically with 'if' so for example... when a user enters a time and the timer get's to the timer it stops... so far my coding is like this...
private void startTimerActionPerformed(java.awt.event.ActionEvent evt) {
javax.swing.Timer tm = new javax.swing.Timer(100, new ActionListener()
{
public void actionPerformed (ActionEvent evt) {
AddOneActionPerformed(evt);
}
});
tm.start();
int getTM,getM,getTS,getS,Secs,tenSec,Mins,tenMin;
getTM = Integer.parseInt(enterTenMins.getText());
getM = Integer.parseInt(enterOneMins.getText());
getTS = Integer.parseInt(enterTenSecs.getText());
getS = Integer.parseInt(enterOneSecs.getText());
tenMin = Integer.parseInt(tenMins.getText());
Mins = Integer.parseInt(oneMins.getText());
tenSec = Integer.parseInt(tenSecs.getText());
Secs = Integer.parseInt(oneSecs.getText());
}
and AddOneActionPerformed(evt) is
private void AddOneActionPerformed(java.awt.event.ActionEvent evt) {
int dd,Secs,tenSec,Mins,tenMin;
tenMin = Integer.parseInt(tenMins.getText());
Mins = Integer.parseInt(oneMins.getText());
tenSec = Integer.parseInt(tenSecs.getText());
Secs = Integer.parseInt(oneSecs.getText());
dd= Integer.parseInt(digitValue.getText());
dd= dd+1;
if (dd==10)
dd = 0;
if (Secs == 10)
Secs = 0;
if (dd==0)
Secs=Secs +1;
if (tenSec>=6)
tenSec = 0;
if (Secs==10)
tenSec=tenSec +1;
if (Mins==10)
Mins = 0;
if (tenSec==6)
Mins=Mins+1;
if (tenMin>=6)
tenMin=0;
if (Mins==10)
tenMin=tenMin+1;
String ss = Integer.toString(dd);
digitValue.setText(ss);
String ff = Integer.toString(Secs);
oneSecs.setText(ff);
String gg = Integer.toString(tenSec);
tenSecs.setText(gg);
String hh = Integer.toString(Mins);
oneMins.setText(hh);
String jj = Integer.toString(tenMin);
tenMins.setText(jj);
showDigitActionPerformed(evt);
showOneSecsActionPerformed(evt);
showTenSecsActionPerformed(evt);
showOneMinsActionPerformed(evt);
showTenMinsActionPerformed(evt);
}

You can get the Timer instance from the ActionEvent's getSource() method, and then call stop on it. So,...
// for your Timer's ActionListener
#Override
public void actionPerformed(ActionEvent evt) {
if (someStoppingConditionIsTrue) {
Timer timer = (Timer) evt.getSource();
timer.stop();
} else {
// code to call repeatedly
}
}
Note that you've got two separate issues going on, and should solve them separately. The code above is a way to stop a Timer from within its own ActionListener using some condition. Your other question is how to get user input to allow you to change that condition, and that will involve separate code that is independent of the Timer code above.
Consider in addtion:
Use two JSpinners to for the user's to input minutes and seconds.
Give your class an int totalTime field.
Set this value in your startTimerActionPerformed method.
Have the Timer's ActionListener decrement this value based on measured elapsed time using the differences in calls to System.getSystemTime().
Calculate get the difference between the totalTime and elapsedTime (it will be in milliseconds), say called timeLeft
Calculate your minutes and seconds from timeLeft.
Then display these values in a JLabel using a formatted String, say something like String.format("%02d:%02d", minutes, seconds).
When the timeLeft == 0, that's when you stop your Timer.

How to do an array of timers in java

I know I am probably way off here, but I am trying to create a timer array so that mytimer[0] mytimer[1], mytimer[2], etc... all fire off at a different interval, with diffrerent events sent to a server. Any ideas? The for loop value of 6 is an organic number for testing purposes only. This number would later be decided base on a setting from the program's xml file.
Timer mytimers[] = new Timer[6];
for(int i = 0;i < 6;i++){
final int mytime = i;
mytimers[i].scheduleAtFixedRate(new TimerTask() {
#Override
public void run() {
//do action
sendData("Timer " + mytime + " fired");
}
}, 10000, i*1000);
}

Timer mytimers[] = new Timer();
I'm assuming this is the line that doesn't work? You can't initialize an array with an object; initialize it with an array:
Timer mytimers[] = new Timer[6];
Making another guess, you're also not initializing the individual timers:
mytimers[i].scheduleAtFixedRate(new TimerTask() {
At this point mytimers[i] isn't set to anything, so how can you call scheduleAtFixedRate on it? Initialize it first:
mytimers[i] = new Timer();
mytimers[i].scheduleAtFixedRate(new TimerTask() {
EDIT:
Your "IllegalArgumentException: Non-positive period." is because on the first time through the loop, i = 0, so i * 1000 = 0, and the period can't be 0 ("run this event every 0 zero seconds").
Start with i = 1 and it should be fine.

Have you thought about just doing one timer, and the putting all the different events in some sort of (if timeElapsed % timerinterval[1] == 0) and then that way you can simulate the different times by using just one timer. Then you only need an array of integers with the timer interval.

Use this:
Timer mytimers[] = new Timer[6];
for(int i = 0;i < 6;i++){
mytimers[i] = new Timer();
final int mytime = i;
mytimers[i].scheduleAtFixedRate(new TimerTask() {
#Override
public void run() {
//do action
sendData("Timer " + mytime + " fired");
}
}, 10000, i*1000);
}
The problem is, you are calling the Timer() constructor on an array and never initializing your individual timers. Rather, you should initialize the array as an array and the individual timers as timers.