如何做出异常通知用户他们输入的数字超出范围？

Question

public static void main(String[] args) {

    Scanner scan = new Scanner(System.in);

    int answer = 28;
    int attempts = 0;
    boolean condition = false;

    System.out.println("Guess a Number 1 - 50:");
    
    do {
        condition = true;
        try {
            int input = scan.nextInt();
            scan.nextLine();
            
            if(input > answer) {
                System.out.println("Too Big");
                System.out.println(); //Spacing
                System.out.println("Guess a Number 1 - 50:");
                attempts++;
            } else if (input < answer) {
                System.out.println("Too Small");
                System.out.println(); //Spacing
                System.out.println("Guess a Number 1 - 50:");
                attempts++;
            } else {
                int totalA = attempts + 1;
                System.out.println(); //Spacing
                System.out.println("Congratulations! "+ "You attempted " + totalA + " times." );
            } 
            
        } catch (InputMismatchException e) {
            System.out.println("Numbers only");
            System.out.println(); //Spacing
            System.out.println("Guess a Number 1 - 50:");
            condition = true;
            scan.nextLine();
        } 
        
    } while(condition);



}

Answer 1

我认为非常重要的一点是，您应该知道可以创建自己的exception类，这些类具有特定的消息和用途。

例如：

public class NumberTooHighException extends Exception { 
    public NumberTooHighException() {
        super("The number inputted is wayyyy to high...");
    }
}

然后，您可以将异常与其他异常一样使用：

if(input > 50)
{
    throw new NumberTooHighException(); // Here you throw it...
}