Getting Data From a class without making an instance of the class

[cpu2007]

Hello everyone,
I was wondering if this process was possible as making an instance of a class that has GUI properieties creates another window when I make the instance of that class.

What I am trying to do is simulating people arriving at a till and leaving it.
I have a
-SuperMarketGUI class which is the class that has all the GUI proprieties value(such as frame,JTextArea,JButton etc)
-ThreadStarted class which is called when the start Button on the SuperMarketClass is pressed.
-Checkout class which process the simulation data

public class ThreadStarter extends Thread {
    public ThreadStarter()
    {
    	
    }
	Checkout chk=new Checkout();
	public void run()
	{
		
		try {
				for(int t=2;t<=10;t++)
				{
						chk.simulation(1,t);
			  
			  sleep((int)(Math.random()*1000));
				}
			} catch (Exception e) 
				{
 			  System.err.println(e);
 			  e.printStackTrace();
				}
						
	}
	public void finish()
	{
	
		
	}
		
}

The code above runs in a for loop once the start button is pressed from another class; it calls the simulation method which is in the Checkout class.

Now I have this simulation method that generates some data(some integers and some strings).
I want that data to be displayed in the JTextArea of my SuperMarketGUI everytime the simulation method is called.

public String simulation(int i,int t)
	{
	    //for (int t=2; t<=10; t++) //number of time-steps in the simulation.
	    //{
	        rndNumber =(int) (Math.random()*6+1); // generates random number between 1 and 6.	      
	        if (rndNumber==4) 
	        {            
	             // if rndNumber is 4, t is added to a queue.
	                tillQueue.add(String.valueOf(t));
	                currentLen++;
	        }
	        else if ((rndNumber==1 || rndNumber==3) && tillQueue.peek()!=null)
	        {	            	           
	            tillQueue.remove();
	            currentLen--;
	         }
	        
	        if(tillQueue.isEmpty())
	        {    
	        	date=dt.getDate();
	        	time=dt.getTime();
	            System.out.println(date+"\t"+time+"\t" +t + "\t" + rndNumber + "\t" + "Queue is empty");
	            //smGUI.setData(date, time, String.valueOf(rndNumber), "Queue Is Empty", i);
	            lengthList.add(new Integer(currentLen));  //using  wrapper
	            return ("\n"+date+"\t"+time+"\t"+rndNumber+"\t"+"Queue Is Empty");
	        }
	        else
	        {         
	            System.out.println(date+"\t"+time+"\t"+t + "\t" + rndNumber+"\t" + tillQueue.toString() );
	            //smGUI.setData(date, time, String.valueOf(rndNumber), tillQueue.toString(), i);
	            smGUI.info[i].append("\n"+date +"\t"+time+"\t"+ String.valueOf(rndNumber)+"\t"+ tillQueue.toString());
	            lengthList.add(new Integer(currentLen));  //using  wrapper
	            return ("\n"+date+"\t"+time+"\t"+rndNumber+"\t"+tillQueue);
	        }
	        
	    }

How can I do that?

Thank you

[dlorde]

If you want have data from a thread displayed in a GUI component, use SwingWorker instead of a plain thread. It's a thread enhanced to communicate with the Swing event dispatch thread without jamming it. Check out the examples in the API docs, and the tutorial here.

Today, most software exists, not to solve a problem, but to interface with other software...
I. O. Angell

[cpu2007]

Thank you for the links, they are really useful.