From the switch inside do, but there is no Boolean value. Is this possible? Java

So the code is about the restriction of giving input in do while

Maybe it may not have Booleans, or it may change or add something I don't know yet Sorry, I'm trying to find an answer, but what I see is just about a loop around the layout That's not the truth.

Scanner kb = new Scanner(system.in);
    // c = continue
    char c;
    // attempt to limit the input to 3 times
    int attempt = 3;
    // option = op
    int op = 0;

    do {
        do{
            System.out.println("Choose continue[0] or go out[1].");
            while  (!kb.hasNextInt()) {
                kb.nextLine();
                System.out.println("It's not a number.");                   
            }
            op = kb.nextInt();
        } while ( op <= -1 || op >= 2 );

        switch (op) {
        case 0:
            System.out.println("Continue!");
            break;
        case 1:     //here I tried; attempt = -1  
            break;  //is where I think it needs to be something
        default:
            break;
        }

        System.out.println("Do you wanna try again,"+attempt+" less?[c]+enter\n"
                + "Any other key + enter to exit.");
        c = kb.next(".").toUpperCase().charAt(0);
        attempt--;
    } while ( attempt > 0 && ( c == 'C' ) );
            //here also to put !( op == 0 )
    kb.close();

Solution

If the user selects 0, you just need to continue

Scanner kb = new Scanner(system.in);
// c = continue
char c = 'a';
// attempt to limit the input to 3 times
int attempt = 3;
// option = op
int op = 0;

do {
    do{
        System.out.println("Choose continue[0] or go out[1].");
        while  (!kb.hasNextInt()) {
            kb.nextLine();
            System.out.println("It's not a number.");
        }
        op = kb.nextInt();
    } while ( op <= -1 || op >= 2 );

    switch (op) {
        case 0:
            System.out.println("Continue!");
            System.out.println("Do you wanna try again,"+attempt+" less?[c]+enter\n"
                    + "Any other key + enter to exit.");
            c = kb.next(".").toUpperCase().charAt(0);
            attempt--;
            break;
        case 1:
            attempt = -1;
            break;
        default:
            break;
    }
} while ( attempt > 0 && ( c == 'C' ) );
kb.close();