Exception handling that never ends...

Question

Hi,
I've been putting the finishing touches on a project I'm working on, and right now I'm "fixing" some of the error handling. I realized that lots of times when I catch an exception, the program never returns to where it left off. Most of these errors would normally be fatal, but since it's important that this particular application does not terminate (ever) I basically just call a method in the main class that resets the application.
The problem, I'm thinking, is that java keeps a place on the stack to return to the statement after the error occurred -- and since this will never happen, I can imagine a lot of unnecessary placeholders eventually overflowing the stack. This would be bad since it's our plan to have this application running on our shop floor for days/months/years at a time with minimal intervention!
But I'm fairly new to java, and maybe I'm just paranoid. Is my understanding of this situation correct? Can I avoid it?
Thanks for any input.

Answer 1

Okay, here is some code. By the way, only on unrecoverable errors do I want to log the user off and reset the application. The reason I'm doing this is because 1) I don't want the application to exit 2) It's possible that the problem is with that particular users account, and the next user might be okay. This is an application running in a kiosk where people will be lining up to use it, and if it can at all stay up it ought to!
One final note before I paste in the code... My application is admittedly not as robust as it could be, but only because my database interface is really an XML API provided by a third-party. The API is limited, so there are only so many things I can do to recover from an error!
Ok, here's some code. It's not my actual application since that would be thousands of lines of code, but it's an example application I set up that illustrates my problem. It simulates a logon and tries to do 3 transactions but fails on the second one. At that point I would like it to simply "reset" itself for the next user and never do the third transaction, but the third transaction inevitably gets done. What do you think?
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class MainClass
     private class MyDialog extends JDialog implements ActionListener
          private JButton myButton = new JButton();
          MyDialog(String buttonText)
               this(null, buttonText, true, buttonText);
          public MyDialog(JFrame parent, String title, boolean modal, String buttonText)
               super(parent, title, modal);
               myButton.setText(buttonText);
               myButton.addActionListener(this);
               this.setSize(400,400);
               this.getContentPane().setLayout(new GridBagLayout());
               this.getContentPane().add(myButton);
          public void actionPerformed(ActionEvent e)
               this.hide();
     MyDialog logon = new MyDialog("Logon");
     MyDialog form = new MyDialog("Do some stuff");
     public MainClass()
     public static void main(String[] args)
          MainClass m = new MainClass();
          System.out.println("Logging on...");
          m.logon.show();
          System.out.println("Showing form...");
          m.form.show();
          for (int index = 1; index <= 3; index++)
               try
                    System.out.println("Doing transation " + index + "...");
                    m.doTransaction(index);
               } catch (Exception e)
                    System.out.println("Resetting due to error...");
                    m.reset();
          m.logoff();               
          System.exit(0);
     private void reset()
          logoff();
          System.out.println("Loggin on...");
          logon.show();
          System.out.println("Showing form...");
          form.show();
     private void doTransaction(int data) throws Exception
          System.out.println("Sending data to database...");
          //Simulate an error occurring
          if (data % 2 == 0)
               System.out.println("Error occurred!");
               throw new Exception();
     private void logoff()
          System.out.println("Logging off...");