How can i use a private method in a public method to check Validity?
private boolean isValid(int aRating)
{

  return aRating >= 1 && aRating <= 10;

}

                or

    private boolean isValid(int aRating)
{

  if (aRating >=1 && aRating <=100
      return true;
  else
      return false

}

public void setRating(int aRating)
{
   if (isValid() == true)
       rating = aRating;

}

public void setRating(int aRating)
     {
       if (isValid(aRating))
          rating = aRating;
     }

public void setRating()
{
    Scanner keyboard = new Scanner(System.in);
  if (isValid(aRating))
      rating = keyboard.nextInt();
}

public void setRating(int aRating)
{
   if (isValidRating(aRating))
       this.rating = aRating;
}

public void setRating(int aRating)
{
    if (isValidRating(aRating))
        this.rating = aRating;
    else
        throw new IllegalArgumentException("Invalid rating.");
}

public void setRating(int rating) {
  checkRating(rating);
  this.rating = rating;
}

private void checkRating(int rating) {
  if (!(1 <= rating && rating <= 10)) {
    throw new IllegalArgumentException("Invalid rating: " + rating);
  }
}