Method is running 3 times

Question

I created this method for a validation when the user will type the option that appears on the screen:

private int menu;
private int menuImprimir;

public int getMenu() 
    {
        return menu;
    }
    public void ativarStatus() 
    {
        this.status = "Ativado";
    }

   public void menuImprimir() 
    {
        System.out.println("Deseja Imprimir os dados?" +
                "\n1 - Sim" + 
                "\n2 - Não");       
                this.menuImprimir = input.nextInt(); 

                while(this.menuImprimir < 1 || this.menuImprimir > 2) 
                {
                    System.out.println("\nErro! - Digite uma opção válida");

                    menuImprimir();
                }

                switch(this.menuImprimir) 
                {
                case 1:
                    imprimir();
                    break;
                case 2:
                    System.out.println("Obrigado! ... ");
                    break;
                default:
                    System.out.println("Opção inválida!\nDigite novamente: ");
                    break;
                }
    }

If the client type the option other than 0 and 1 it stays inside the while asking him to enter the correct option. But if the client type 3 times the wrong option and on the fourth he type the correct system is printing System.out.println("Concluído com Sucesso!");"3 times to later exit the method, even if I put this Return..

Answer 1

I’ll guess what the method getMenu ago:

• writes the options
• asks the user to enter a number
• le and returns the number typed

Then, every time it is called, it will require a new digit. On that line while(getMenu() < 0 || getMenu() > 1) will ask for the digit for the first time and compare it to zero. If it is not smaller, it will ask for a second digit to compare with 1. And, within the loop, the method is called by third time. It’s definitely not what you want to do...

The response of the first call must be stored in a variable for then the content of that being compared, ie the method is called only once... only being called again when a new value is listed.

Example, very much simplified (using the question code structure):

int menu = getMenu();
while (menu < 0 || menu > 1) {
    System.out.println(MENSAGEM_ERRO);
    if (menu == 0) {
        ...
        return;
    }
    if (menu == 1) {
        ...
        return;
    }
    ...

    menu = getMenu();
}

A little better structure would be:

while (true) {
    int menu = getMenu();
    if (menu == 0) {
        ...
        return;
    }
    if (menu == 1) {
        ...
        return;
    }
    System.out.println(MENSAGEM_ERRO);
}

(a little) More 'advanced'' :

int menu;
while ((menu = getMenu()) < 0 || menu > 1) {
    System.out.println(MENSAGEM_ERRO);
}
switch (menu) {
    case 0:
        ...
        break;
    case 1:
        ...
        break;
    default: throw IllegalArgumentException("Error menu: " + menu);
}

Other, better option (IMHO): the method getMenu test the given value, only returning valid values...