/*
 * Switch Case Break where switch is an Integer
 * Case values must be literals (or variables declared as final)
 * while loop with switch to validate good input data.
 * Use of the default value with switch
 * Use of boolean flag value to ensure exit out of the while loop
 */
package caseswitchbreak;

import javax.swing.JOptionPane;

public class CaseSwitchBreak {

    public static void main(String[] args) {
        
        boolean done = false;
        String choiceSt = JOptionPane.showInputDialog(null, "Enter your choice");
        int choice = Integer.parseInt(choiceSt);
        
        while (done == false){
        
        switch(choice){
            case 1: {
                System.out.println("Doing One");
                done = true;
                break;
                }   
            case 2: {
                System.out.println("Doing Two");
                done = true;
                break;
                }
            case 3:{
                System.out.println("Doing Three");
                done = true;
                break;
                }
            case 4: {
                System.out.println("Doing Four");
                done = true;
                break;
                }
            default : {
                System.out.println(choice + " is not a valid choice");
                done = false;
                choiceSt = JOptionPane.showInputDialog(null, "Enter your choice again.");
                choice = Integer.parseInt(choiceSt);
            }
                    
        } // end switch
       
    } // end while
        
        System.out.println("This is the end");
    }
    
}
=====================================================================================

OUTPUT

run:
7 is not a valid choice
8 is not a valid choice
9 is not a valid choice
Doing Two
This is the end
BUILD SUCCESSFUL (total time: 11 seconds)