如何重试/捕获输入不匹配异常而不会被无限循环捕获

问题描述：

我正在尝试从用户那里获取输入，以构建2d地雷的哭泣游戏的网格，
，当我将有效值传递给Scanner时，过程进行得很顺利，但是当我尝试无效的事情时，过程就进行了通过无限循环，即使try块是try资源，也应该尝试每次重新尝试关闭扫描仪，当它无限期地在catch上打印字符串时，听起来并没有关闭

I'm trying to take input from the user to build a grid for a 2d mine's weeper game, the process goes pretty smooth when I pass valid values to the Scanner, but when I try invalid things it goes through infinite loop even the try block is try with resources which should close the scanner with each a new try, it sounds it doesn't close it when it prints the string on the catch infinitely

int gridSize = 0;
    System.out.println("how much do you want the grid's size");
    try (Scanner scanner = new Scanner(System.in)) {
        while (gridSize == 0) {
            gridSize = scanner.nextInt();
            scanner.next();
        }
    } catch (NoSuchElementException e) {
        System.out.println("try again");
    }

答

您发现错误了例外-如果输入的不是 int ，则为 InputMismatchException 会被抛出。但是无论如何，使用 hasNextInt（） ：

You're catching the wrong exception - if the input isn't an int, an InputMismatchException will be thrown. But regardless, this can be made easier by using hasNextInt():

try (Scanner scanner = new Scanner(System.in)) {
    while (!scanner.hasNextInt()) {
        System.err.println("Try again, this time with a proper int");
        scanner.next();
    }
    gridSize = scanner.nextInt();
}

如何重试/捕获输入不匹配异常而不会被无限循环捕获

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