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Java TimerTask in While Loop [duplicate]

I am using java.util.Timer class and I am using its schedule method to perform some task, but after executing it for 6 times I have to stop its task.
How should I do that?

Keep a reference to the timer somewhere, and use:
timer.cancel();
timer.purge();
to stop whatever it's doing. You could put this code inside the task you're performing with a static int to count the number of times you've gone around, e.g.
private static int count = 0;
public static void run() {
count++;
if (count >= 6) {
timer.cancel();
timer.purge();
return;
}
... perform task here ....
}

Either call cancel() on the Timer if that's all it's doing, or cancel() on the TimerTask if the timer itself has other tasks which you wish to continue.

You should stop the task that you have scheduled on the timer:
Your timer:
Timer t = new Timer();
TimerTask tt = new TimerTask() {
#Override
public void run() {
//do something
};
};
t.schedule(tt,1000,1000);
In order to stop:
tt.cancel();
t.cancel(); //In order to gracefully terminate the timer thread
Notice that just cancelling the timer will not terminate ongoing timertasks.

Terminate the Timer once after awake at a specific time in milliseconds.
Timer t = new Timer();
t.schedule(new TimerTask() {
#Override
public void run() {
System.out.println(" Run spcific task at given time.");
t.cancel();
}
}, 10000);

Timer function adding an extra Timer on each call

Can anyone help me with my two Timer Functions:
The first one just makes the timer while canceling any previous one out first,
The second one just handles Cancelling the Timer
public void startInterval(int delay, int time, final String eventName){
cancelInterval();
mInterval = new Timer();
mInterval.scheduleAtFixedRate(new TimerTask() {
#Override
public void run() {
Log.i("timer", "Interval");
sendEvent(eventName, Arguments.createMap());
}
}, delay, time);
}
public void cancelInterval() {
if (mInterval != null){
mInterval.cancel();
mInterval.purge();
}
mInterval = null;
}
The problem is that the timer is multiplying every time I call it.
The first time I call, it works as intended, but after a few calls it ends up adding an extra timer per call

restart timers for one operation in java

I have one button include timer, but when I clicked the button again, same timer start counting twice. I want to stop the counter every time and restart it. how can I do it?
#FXML
private void handleButtonAction(ActionEvent event) {
int cnt=0;
Timer timer=new Timer();
TimerTask task=new TimerTask() {
#Override
public void run() {
cnt++;
System.out.println("task: "+cnt);
}
};
timer.schedule(task, 0, 3000);
}
when I clicked the button again, it calls system out twice.

By calling Timer timer = new Timer(); inside handleButtonAction you create a new Timer with every click.
You have to declare the Timer outside the method, then you can restart it by clicking the button like:
Timer timer;
private void handleButtonAction(ActionEvent event) {
int cnt=0;
timer = new Timer();
TimerTask task = new TimerTask() {
#Override
public void run() {
cnt++;
System.out.println("task: "+cnt);
}
};
timer.schedule(task, 0, 3000);
}
This way you always restart the same timer.

Java - Reusing Timer Object after calling cancel

I have an application in Java where I need to schedule a TimerTaskwhich will be executed after 500ms , however if a certain event occurs, I must reset the timer for this task (so that we must wait another 500ms for it to execute). I have a timer declared for the whole class. I use the following code:
public static void main(String[] args) {
if (curr_pck == my_pck) {
timer.cancel();
timer.purge();
timer = new Timer();
timer.schedule(new TimerTask() {
#Override
public void run() {
myTask();
}
}, 500);
}
}
public static void myTask() {
timer.cancel();
timer.purge();
timer = new Timer();
timer.schedule(new TimerTask() {
#Override
public void run() {
myTask();
}
}, 500);
//EXECUTE CODE WHICH ISN'T RELEVANT TO THE QUESTION
}
I know that if I use timer.cancel() I can't reuse the timer object, however I thought reinitialising it in the line timer = new Timer() should solve this issue. Is there any way around this?
EXCEPTION on line timer.schedule(new TimerTask() { inside myTask() function:
java.lang.IllegalStateException: Timer already cancelled.

Create a class Timerr with the appropriate methods. Then access it as if it were a normal timer.
public class Timerr
{
private Timer timer;
public Timerr()
{
timer = new Timer();
start();
}
public void start()
{
timer.schedule(new TimerTask()
{
#Override
public void run()
{
System.out.println("hi");
}
}, 500);
}
public void reset()
{
timer.cancel();
timer.purge();
start();
}
}
Create instance
private Timerr timer = new Timerr();
Do your reset
if(condition)
{
timerr.reset();
}

You may want to check out Java's Swing timer. It works somewhat differently and you may have to write an internal class or an actionlistener, but the Swing timer includes .stop() and .restart(), which seem like they would work better in your application.

Android timer one thread only

I'm having problem with Android timer's scheduleAtFixedRate option.
Timer timer = new Timer();
TimerTask myTimerTask = new TimerTask() {
public void run() {
...
}
};
timer.scheduleAtFixedRate(myTimerTask, 0, 5000);
This snippet is doing bad things for me. It's executed in the service so every time method is called timer creates a new thread and executes the same code while the old thread is still running; that creates performance problems. I need to run the code in the run() method every 5 seconds but I want the old task to be canceled. Is there any way to handle this problem ?

You can use the timer.cancel() to stop the timer.
For example, I had an end button to finish the timer early:
finishEarlyButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View arg0) {
timer.cancel();
}
});