Scanning double with nextDouble

Question

I'm learning Java and I got some problems when I try input double floating numbers.

Like this.

import java.util.Scanner;

class Program {
     public static void main (String[] args) {
           Scanner inp = new Scanner(System.in);
           double number = inp.nextDouble();
           System.out.println(number);
     }
}

If I enter 1000 my output will be 1000.0. But if I enter 1000.0, I got this error:

Exception in thread "main" java.util.InputMismatchException
    at java.util.Scanner.throwFor(Scanner.java:909)
    at java.util.Scanner.next(Scanner.java:1530)
    at java.util.Scanner.nextDouble(Scanner.java:2456)
    at test.Test.main(Test.java:6)
Java Result: 1

How could I solve this?

@MarounMaroun I think it depends on the country where you are. I'm in Italy and decimal numbers are written with a comma, not a dot, so if i enter `1000.0` i get an `InputMismatchException`, if i enter `1000,0` everything goes fine. — BackSlash, Sep 22 '13 at 13:51
yeah I also heard this that in france `,` works as `.` in numbers , @BackSlash with which locale you checked it ? — exexzian, Sep 22 '13 at 13:55
@sansix I checked with the default locale, which is `Locale.ITALY` for me — BackSlash, Sep 22 '13 at 14:00

vikingsteve · Accepted Answer · 2013-09-22T15:05:01.360

1

It's likely due to Locale differences between 1000.0 and 1000,0... so you could try this:

Scanner inp = new Scanner(System.in);
inp.useLocale(Locale.ENGLISH);

I hope this helps.

edited Sep 22 '13 at 15:05

answered Sep 22 '13 at 13:53

vikingsteve

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Scanner doesn't have such method, it's `useLocale` – BackSlash Sep 22 '13 at 13:57
But there is a a problem. cannot find symbol: symbol: variable Locale location: class Program ---- – Alvadorn Sep 22 '13 at 14:24
@Alvadorn You have to import `java.util.Locale` – BackSlash Sep 22 '13 at 14:30
Now it works. Thank you! – Alvadorn Sep 22 '13 at 14:38
@BackSlash Thanks for pointing out my typo. Alvadorn - glad it works! – vikingsteve Sep 22 '13 at 15:05

Scanning double with nextDouble

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