Saving/restoring treeSet

Question

I've got a customer database using TreeSet API. I'm trying to make a method for saving and restoring the treeset, but I'm a little confused. Any help would be appreciated:
Thanks
public class TreeSetProject {
   public static void main(String[] args) throws Exception {
     //main method
          int menuCode, add, delete;
          char check;
          boolean search = false, repeat = false, done = false, exist = false;
          TreeSet customer = new TreeSet();
         while (!done) {
          //loops until boolean done becomes true
              menuCode = Integer.parseInt(JOptionPane.showInputDialog(null,
                   "1. Add customer"
                        + "\n2. Delete customer"
                             + "\n3. Search for a customer"
                                  + "\n4. List all customers"
                                       + "\n5. Save your progress"
                                            + "\n6. Restore from last save point"
                                                  + "\n7.Delete all entries"
                                                      + "\n **Enter 0 to end program**"
                                                           + "\n Please enter a choice: "));
               //Creates choices in menu
               switch (menuCode) {
               //creates switch statment for menu
                    case 1:
                         String customerToAdd = JOptionPane.showInputDialog(null,
                              "Customer's name: ");
                         repeat = customer.contains(customerToAdd);
                         if (repeat == false)
                              customer.add(customerToAdd);
                              JOptionPane.showMessageDialog(null, customerToAdd + " was successfully added to the list");
                         else
                              JOptionPane.showMessageDialog(null, "Sorry, but " + customerToAdd + " is already in the list");
                         break;
                         //Allows user to add customers and checks for duplicates
                    case 2:
                         String customerToDelete = JOptionPane.showInputDialog(null,
                              "Customer to delete: ");
                         exist = customer.contains(customerToDelete);
                         if (exist == true)
                              customer.remove(customerToDelete);
                              JOptionPane.showMessageDialog(null, customerToDelete + " was successfully removed from the list");
                         else
                              JOptionPane.showMessageDialog(null, "Sorry, but " + customerToDelete + " does not exist");
                         break;
                         //Allows user to delete customers and checks to make sure the record exists
                    case 3:
                    String customerToSearch = JOptionPane.showInputDialog(null,
                              "Customer to search for: ");
                         search = customer.contains(customerToSearch);
                         if (search == true)
                              JOptionPane.showMessageDialog(null, customerToSearch + " is in the database");
                         else
                              JOptionPane.showMessageDialog(null, "Sorry, but " + customerToSearch + " is not in the database");
                         break;
                         //Allows user to search for a customer
                    case 4:
                         JOptionPane.showMessageDialog(null, customer.toArray());
                         break;
                         //prints a list of all data
                    case 7:
                         customer.removeAll(customer);
                    break;
                    //removes all entries if case 7 is chosen     
                    default:
                         JOptionPane.showMessageDialog(null, "Bad input. Read the choices carefully!");
                         //Tells user to retry their selection if they don't enter a choice from 0-7
               }//ends switch statment     
          }//ends while loop
     }//ends main method
}//ends class

Answer 1

dazeman wrote:
I've got a customer database using TreeSet API. I'm trying to make a method for saving and restoring the treeset, but I'm a little confused. Any help would be appreciated:
Thanks
...Ok, but what is your question?
By looking at the title of your thread "Saving/restoring treeSet" I'd say: have a look at Serialization:
http://www.deitel.com/articles/java_tutorials/20050923/IntroductionToObjectSerialization.html
But if you have a specific question about the code you posted, feel free to ask it here.