Question

do {

    try {
        System.out.print("Please enter the hour:");
        hour = consoleScanner.nextInt();
        if (hour < 1 || hour > 12) {
            throw new InvalidHourException();
        }

        System.out.print("Please enter the minute:");
        minute = consoleScanner.nextInt();
        if (minute < 0 || minute > 59) {
            throw new InvalidMinuteException();
        }
        if (minute <= 9)
            zero = "0";

        System.out.print("Please enter either \"AM\" or \"PM\":");
        meridiem = consoleScanner.next();
        if (!(meridiem.equalsIgnoreCase("AM"))
                && !(meridiem.equalsIgnoreCase("PM"))) {
            throw new InvalidMeridiemException();
        }

    } catch (InvalidHourException hourEx) {
        System.out.println(hourEx.getMessage());
        consoleScanner.nextLine();
        errorOccured = true;
    } catch (InvalidMinuteException minuteEx) {
        System.out.println(minuteEx.getMessage());
        consoleScanner.nextLine();
        errorOccured = true;
    } catch (InvalidMeridiemException meriEx) {
        System.out.println(meriEx.getMessage());
        consoleScanner.nextLine();
        errorOccured = true;
    }

} while (errorOccured);
System.out.println(hour + ":" + zero + minute + meridiem + " is a valid time.");
consoleScanner.close();

}
}

这是我的while while循环。输出是：

Please enter the hour:8
Please enter the minute:60
Please enter a minute between 1 to 60
Please enter the hour:

为什么它会跳回到小时而不是分钟？ catch语句中有什么问题吗？

Answer 1

由于您只有一个try块，并且只要抛出任何异常就重复它，在捕获异常后，即使问题不是小时输入，也会执行提示小时的代码。 / p>

为了不重复请求已经有效的输入，你需要为3个输入中的每一个输入一个单独的while循环+ try-catch块。

除此之外，当输入有效时，您应将errorOccured设置为false。否则你永远不会离开循环。

为什么我的代码会在异常出现后不断重复？

1 个答案: