Thread: while looping a swing worker does not display results on jtable?

hi,
I am using swing worker to update my GUI in edt. I have the code below. when I run the code without the while loop it works,
whereas when I run with the while loop it falis , why is it so ?

 
import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.util.List;
import java.util.Scanner;
import java.util.Vector;
import java.util.concurrent.ExecutionException;
 
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingWorker;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableModel;
 
public class App 
{ 	 
	     static JFrame frame = new JFrame("Random Data Demo");
	     static JTable table =  new JTable();
	     static DefaultTableModel tableModel = new DefaultTableModel();
	 	 static Scanner sc=new Scanner(System.in);
 
	   public static void main(String[] args) throws Exception {
	        EventQueue.invokeLater(new Runnable() {
	            @Override
	            public void run() 
	            {            	
	               while(true)                                                     ////// while loop ---
	               {
 
	            	System.out.println("Write message here: ");									
	     			String message = sc.nextLine();
	     			System.out.println("Message is: "+message);
 
	            	Swingwor mainWorker = new Swingwor(table,message);
	                mainWorker.execute(); 
 
	                init();
 
	               }
	            }
	        });
	    }
 
	   private static void init() {
		   //execTask();
		 // JFrame frame = new JFrame("Random Data Demo");
	       frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
	      frame.setSize(600,600);
 
	    //	DefaultTableModel model = new DefaultTableModel();
	    	//JTable table =  new JTable(model);
	    	table.setModel(tableModel);
 
	    	table.repaint();
	    	JScrollPane scrollPane = new JScrollPane(table);
 
	    	JPanel panel = new JPanel(new BorderLayout());
	    	//Swingworker mainWorker = new Swingworker(table);
           // mainWorker.execute();
 
	    	panel.add(table.getTableHeader(), BorderLayout.PAGE_START);
	    	panel.add(scrollPane, BorderLayout.CENTER);
	    	//getContentPane().add(panel);
              frame.add(panel);
	          frame.setVisible(true);
	    }
 
	 //  private static void execTask() 
	  // {	  
		//   Swingwor mainWorker = new Swingwor(table);
	//	   mainWorker.execute(); 
 
   //   }
}
 
 
class Swingwor extends SwingWorker<TableModel,TableModel>
{
 
	Object data[][]=null;
    private final JTable table;
    int i,r;
    String p;
    String message=null;
    Object col[] = {"Sensor","Values","Arrival_Time","Status",""};
 
    public Swingwor(JTable table, String message) {
        this.table = table;
        this.message = message;
    }    
    @Override
    protected TableModel doInBackground() throws Exception 
    {     	   	
			if(!message.equals("ITS EMPTY"))
			{
				String[] parts = message.split("\t");
		            data = new Object[parts.length / 4][5];
				for (i = 0, r = 0; r < data.length; r++) 
				{                        	  						
					data[r][0] =  parts[i++];
				   //data[r][1] =  new Double(parts[i++]) ;
				    data[r][1] =  parts[i++] ;
				    data[r][2] = parts[i++];
				    data[r][3] = parts[i++];
				    p=(String) data[r][3];
				   // w = (String) abc(p);
				    data[r][4]=Boolean.parseBoolean(p) ;
				  System.out.println(data[r][4]);
				}               
				//System.out.println(java.util.Arrays.deepToString(data));
             //Display Table     
                  }
			DefaultTableModel tableModel = new DefaultTableModel(data, col);
	        tableModel.setDataVector(data, col);
			 return tableModel;
          }
 
 
    @Override
    protected void done() {
        try {
            TableModel model = get();
            table.setModel(model);
        } catch (InterruptedException | ExecutionException ex) {
            ex.printStackTrace();
        }
    }
 
 
 
}

fails means : IT dosn't show the values in the jtable... The program executes without errors. input is also given,but the input is not shown in jtable

--- Update ---

u can try executing the program ..

Originally Posted by Norm

Why is setModel() called in 2 places? One call is with an empty model.

Why the loop in run() that is creating panel each time around the loop?

oh !! I again modified the code,solving the above problem.. But still no result ??

import java.awt.BorderLayout;
import java.awt.EventQueue;
import java.util.List;
import java.util.Scanner;
import java.util.Vector;
import java.util.concurrent.ExecutionException;
 
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingWorker;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.TableModel;
 
public class App 
{ 	 
	     static JFrame frame = new JFrame("Random Data Demo");
	     static JTable table =  new JTable();
	 	static JPanel panel = new JPanel(new BorderLayout());
	     static DefaultTableModel tableModel = new DefaultTableModel();
	 	 static Scanner sc=new Scanner(System.in);
 
	   public static void main(String[] args) throws Exception {
	           EventQueue.invokeLater(new Runnable() {
	            @Override
	            public void run() 
	            {     
	              while(true)
	              {
	            	Swingwor mainWorker = new Swingwor(table);
	                mainWorker.execute(); 
 
 
	                init();
	                try {
						Thread.sleep(10000);
					} catch (InterruptedException e) {
						// TODO Auto-generated catch block
						e.printStackTrace();
					}
	              }
	            	}            
	        });
	    }
 
	   private static void init() {
		   //execTask();
		 // JFrame frame = new JFrame("Random Data Demo");
	       frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
	      frame.setSize(600,600);
 
	    //	DefaultTableModel model = new DefaultTableModel();
	    	//JTable table =  new JTable(model);
	    	//table.setModel(tableModel);
 
	    	table.repaint();
	    	JScrollPane scrollPane = new JScrollPane(table);
 
 
	    	//Swingworker mainWorker = new Swingworker(table);
           // mainWorker.execute();
 
	    	panel.add(table.getTableHeader(), BorderLayout.PAGE_START);
	    	panel.add(scrollPane, BorderLayout.CENTER);
	    	//getContentPane().add(panel);
              frame.add(panel);
	          frame.setVisible(true);
	    }
 
	 //  private static void execTask() 
	  // {	  
		//   Swingwor mainWorker = new Swingwor(table);
	//	   mainWorker.execute(); 
 
   //   }
}
 
 
class Swingwor extends SwingWorker<TableModel,TableModel>
{
 
	Object data[][]=null;
    private final JTable table;
    int i,r;
    String p;
	 static Scanner sc=new Scanner(System.in);
    String message=null;
    Object col[] = {"Sensor","Values","Arrival_Time","Status",""};
 
    public Swingwor(JTable table) {
        this.table = table;
     //   this.message = message;
    }    
    @Override
    protected TableModel doInBackground() throws Exception 
    {     	
    	    System.out.println("Write message here: ");									
			String message = sc.nextLine();
			System.out.println("Message is: "+message);
 
			if(!message.equals("ITS EMPTY"))
			{
				String[] parts = message.split("\t");
		            data = new Object[parts.length / 4][5];
				for (i = 0, r = 0; r < data.length; r++) 
				{                        	  						
					data[r][0] =  parts[i++];
				   //data[r][1] =  new Double(parts[i++]) ;
				    data[r][1] =  parts[i++] ;
				    data[r][2] = parts[i++];
				    data[r][3] = parts[i++];
				    p=(String) data[r][3];
				   // w = (String) abc(p);
				    data[r][4]=Boolean.parseBoolean(p) ;
				  System.out.println(data[r][4]);
				}               
				//System.out.println(java.util.Arrays.deepToString(data));
             //Display Table     
                  }
 
			DefaultTableModel tableModel = new DefaultTableModel(data, col);	
	        tableModel.setDataVector(data, col);
	        publish(tableModel);
 
			 return tableModel;
    }
 
 
    @Override
    protected void process(List<TableModel> chunks)
    {
    	TableModel model = null;
		try {
			model = get();
		} catch (InterruptedException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (ExecutionException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
        table.setModel(model);
    }
 
    @Override
    protected void done() {
        try {
            TableModel model = get();
            table.setModel(model);          
        } catch (InterruptedException | ExecutionException ex) {
            ex.printStackTrace();
        }
    }
 
 
 
}

--- Update ---

norm : is it something that the loop is busy executing the job,thats y its not able to update the GUI ??

text from the page includes the following: Every application must have a main method that represents its starting point. This method runs on an initial or startup thread. The initial thread might read program arguments and initiate a few other objects, but in many Swing applications, this thread's primary purpose is to start the application's graphical user interface (GUI). Once the GUI starts for most event-driven desktop applications, the initial thread's work is done....and many other useful things about swing and workers.