//IntCheck1.java
//howto input an int without program-terminating error
//try catch blocks used

import javax.swing.*;

public class IntCheck1 {

    public static void main(String[] args) {
	String input;
	int num=0;   //initialize to fake out compiler
	boolean goodInt;

	goodInt = false;    //not gotten good int yet
	do {
	    try {
		input = JOptionPane.showInputDialog( "Enter an integer" );
		num = Integer.parseInt( input );
		//***parseInt will throw a NumberFormatException if the parameter
		//can not be converted to an int.  Without the catch'ing of it
		//it would cause termination of the program.
		goodInt = true;  //if get this far, is a good int
	    } catch (NumberFormatException e) {
		//some message to user:
		JOptionPane.showMessageDialog(null, "Invalid integer.  Try again");
	    }
	} while (!goodInt);
	
	JOptionPane.showMessageDialog(null, "Got the good int: " + num);

    }
}