ComplexGUIDriver for String Constructor

/* Ricardo Santiago
* 2/20/16
* CSC-112
* ComplexGuiDriver
*/
import javax.swing.JOptionPane;

public class ComplexGuiDriver {

    public static void main(String[] args) {
        final String title = "Complex Numbers GUI";
        System.out.println("Running " + title + ". Have fun!!!");

        do {

            String temp;
            temp = JOptionPane.showInputDialog(null, "Enter 1st complex number", title,
                    JOptionPane.INFORMATION_MESSAGE);
            Complex a = new Complex(temp);
            if (temp == null)
                break;

            temp = JOptionPane.showInputDialog(null, "Enter 2nd complex number", title,
                    JOptionPane.INFORMATION_MESSAGE);
            Complex c = new Complex(temp);
            if (temp == null)
                break;

            Complex ans = null;
            String options[] = { "Add", "Subtract", "Multiply", "Divide", "Absolute Value", "Negate", "Conjugate",
                    "Distance", "Equality", "Greater than", "Less Than", "Quit" };
            int option = JOptionPane.showOptionDialog(null, "Choose Operation", title, JOptionPane.YES_NO_CANCEL_OPTION,
                    JOptionPane.PLAIN_MESSAGE, null, options, 11);
            String output = "(" + a + ")";
            String out = "";
            switch (option) {
            case 0:
                ans = a.add(c);
                output += " + ";
                break;
            case 1:
                ans = a.subtract(c);
                output += " + ";
                break;
            case 2:
                ans = a.multiply(c);
                output += " * ";
                break;
            case 3:
                ans = a.divide(c);
                output += " / ";
                break;
            case 4:
                out += " |" + a + "|  = " + a.abs() + " \n |" + c + "| = " + c.abs() + "";
                break;
            case 5:
                out += "negate " + a + " = " + a.negate() + "\nnegate " + c + " = " + c.negate();
                break;
            case 6:
                out += "conjugate of " + a + " = " + a.conjugate() + "\nconjugate of " + c + " = " + c.conjugate();
                break;
            case 7:
                out += "distance between (" + a + ") and (" + c + ") = " + a.distance(c);
                break;
            case 8:
                out += a + " == " + c + " = " + a.equals(c);
                break;
            case 9:
                out += a + " > " + c + " = " + a.greaterThan(c);
                break;
            case 10:
                out += a + " < " + c + " = " + a.lessThan(c);
                break;

            default:
                break;
            }
            if (option > 11)
                break;

            if (option <= 3) {
                output += "(" + c + ")" + " = " + ans;
                JOptionPane.showMessageDialog(null, output, title, JOptionPane.PLAIN_MESSAGE);

            } else {
                if (option >= 4)
                    JOptionPane.showMessageDialog(null, out, title, JOptionPane.PLAIN_MESSAGE);
            }

            option = JOptionPane.showConfirmDialog(null, "Do you want to do this again?", title,
                    JOptionPane.YES_NO_CANCEL_OPTION, JOptionPane.QUESTION_MESSAGE);
            if (option != JOptionPane.YES_OPTION)
                break;
        } while (true);
    }
}