“线程“主”java.util.InputMismatchException 中出现异常”**

我已经搜索过，但我确实找不到代码中的任何错误，请帮忙！

代码可以编译，但是，这是我想回答问题 3 时遇到的错误：

Exception in thread "main" java.util.InputMismatchException
        at java.util.Scanner.throwFor(Unknown Source)
        at java.util.Scanner.next(Unknown Source)
        at java.util.Scanner.nextDouble(Unknown Source)
        at ForgetfulMachine.main(ForgetfulMachine.java:16)

这是我的代码：

import java.util.Scanner;

public class ForgetfulMachine
{
    public static void main( String[] args )
    {
        Scanner keyboard = new Scanner(System.in);

        System.out.println( "What city is the capital of Germany?" );
        keyboard.next();

        System.out.println( "What is 6 divided by 2?" );
        keyboard.nextInt();

        System.out.println( "What is your favorite number between 0.0 and 1.0?" );
        keyboard.nextDouble();

        System.out.println( "Is there anything else you would like to tell me?" );
        keyboard.next();
    }
}

Scanner如果条目的格式对于扫描仪的区域设置不正确，将引发此异常。特别是，在您的情况下，如果使用了错误的小数分隔符。两个都. and ,是常见的特定于区域设置的小数分隔符。

要了解默认区域设置的小数分隔符是什么，您可以使用：

System.out.println(
    javax.text.DecimalFormatSymbols.getInstance().getDecimalSeparator()
);

也可以看看：

• Scanner#locale() https://docs.oracle.com/javase/8/docs/api/java/util/Scanner.html#locale--
• Scanner#useLocale(Locale) https://docs.oracle.com/javase/8/docs/api/java/util/Scanner.html#useLocale-java.util.Locale-
• DecimalFormatSymbols#getInstance(Locale) https://docs.oracle.com/javase/8/docs/api/java/text/DecimalFormatSymbols.html#getInstance-java.util.Locale-