SwingWorker and Exceptions in doInBackground() function

Question

Hi. I have GUI and task which communicate with database. I have special class with prepared statements fields, data (returned from database) fields, get methods and construcor. Constructor assume one parameter, query data and fill data fields. So in constructor I perform (maybe) long running task. So I made this subclass SwingWorker in which I create instance of my database class. User type some input (serial number to which he wants to show info), confirm, there start the worker thread. However when he type bad input constructor of database class throws InvalidSnException and then I must show him JOptionPane with error message (or database error occurs). But I shouldn't do that from doInBacground() method because it isn't EventDispatcher thread.
public DbOperations doInBackground()
  DbOperations db = null;
  try {
    db = new DbOperations(sn);
  catch(InvalidSnException) {
  catch(SQLException e) {
  catch(Exception e) {
  return db;
}I don't want to create some additional variables to hold error data, because exceptions hold worth information itself (for example SQLException). Do you know any idea how can solve this?

Answer 1

So you mean that when I invoke JOptionPane method in chatch block in SwingUtilities.invokeLater() function, the code that shows JOptionPane will run on EDT?
When I catch InvalidSnException I just want to show error message and continue some loop to let user type input again, but when I catch SQLException I want show error message and exit with System.exit(-1). Should I use invokeAndWait() instead of invokeLater() ?
Thx