getting a boolean value from 'try' in java

Question

With try and catch, the computer knows when something went wrong? Is there a way that in a boolean? or how can I make this loop go on as long as I get an exception?

public static void main(String[] args) {

    Scanner scan = new Scanner(System.in);
    int x = 0;
    System.out.println("Ingresa un número entero entro 0 y 100");
    //do{
        try {
            x = Integer.parseInt(scan.nextLine());
        }
        catch(NumberFormatException e){
            System.out.println("No se ha introducido un valor numérico.\nVuelva a intentarlo:");
        }
    //}while (x scan gets no Integer Input);
}

Answer 1

To use boolean (or some other value) value as loop condition, you should declare it outside try-catch :

Scanner scan = new Scanner(System.in);
boolean b;                                     // <- your boolean
int x = 0;
System.out.println("Enter a number 0 y 100");
do {
    try {
        x = Integer.parseInt(scan.nextLine());
        b = false;                             // <- if ok, set false
    } catch(NumberFormatException e){
        System.out.println("This is not a number. Please retry");
        b = true;                              // <- if catch block is entered, set true
    }
} while (b);