how to create a function to completely quit the program?

Question

I want to completely quit the program after input the number of 0. If user input number of 0, there will show the output of Goodbye, but the program is still running if they input other number, eg. 1. Therefore, how can I completey quit the program after user inputed the number of 0.

   case 0:
         System.out.println("Goodbye.");                       
         break;

Answer 1

System.exit(0) will close the current program with status 0

  case 0:
         System.out.println("Goodbye.");                       
         System.exit(0);