java throw an exception
public static void main(String[] args) { Scanner kb = new Scanner(System.in); System.out.println("Enter a number"); try { double nb1 = kb.nextDouble(); if(nb1<0) throw new ArithmeticException(); else System.out.println( "result : " + Math.sqrt(nb1) ); } catch (ArithmeticException e) { System.out.println("You tried an impossible sqrt"); } }