如何解决Java越界编码错误？

Question

I am trying to create a Times Tables quiz on BlueJ using Java and every time I try and run this code it tells me that there is an out of bounds exception and highlights the starred line of code.

public void getQuestion()
{
    boolean newQuestion;

    Random randomGenerator = new Random();
    int randomInt = 0;
    for (int j=1; j<=12; j++)
    {
        newQuestion=false;
        int i=0;
        while (newQuestion==false)
        {
            randomInt = randomGenerator.nextInt(12);
            randomInt = randomInt + 1;
            while ((chosenArray [i]!=randomInt) && (chosenArray[i]!= randomInt))
            {
                i=i+1;
                ***if (chosenArray[i]==0)***
                {
                    newQuestion = true;
                    chosenArray[i]=randomInt;

                }

            }

        }

    }
    System.out.print(timesTableChosen + " x " + randomInt + " = "); 
}

}

How should I resolve this so that it works? Thanks.

Answer 1

The root cause is that you overindex when increasing i , Use modulo operator % :

i=(i+1) % 12;

BTW, instead of magic numbers, like 12 , I'd use chosenArray.length , always.