How to handle NumberFormatException: null in Java to cancel and exit the program

Question

I have this in my code. The whole program works fine, except when you click cancel from enter name dialog, in which it proceeds to the next dialog box asking for an input of rounds. And finally exits. It's suppose to exit on the first dialog box.

Code with error:

    String iName = JOptionPane.showInputDialog (null, "Enter name:", JOptionPane.PLAIN_MESSAGE);
    int iRounds = Integer.parseInt(JOptionPane.showInputDialog (null, "Enter number of rounds:", JOptionPane.PLAIN_MESSAGE));

Clicking cancel proceeds to this, when it's supposed to exit right away:

Any idea how to fix this error? Thanks!

Answer 1

String iName = JOptionPane.showInputDialog (null, "Enter name:", JOptionPane.PLAIN_MESSAGE);

if( ((iName != null) && (iName .length() > 0)) {
    int iRounds = Integer.parseInt(JOptionPane.showInputDialog (null, "Enter number of rounds:", JOptionPane.PLAIN_MESSAGE));
}