FULL PRODUCT VERSION :
java version "1.8.0_112"
Java(TM) SE Runtime Environment (build 1.8.0_112-b16)
Java HotSpot(TM) 64-Bit Server VM (build 25.112-b16, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Darwin Dos-MacBook-Pro.local 16.1.0 Darwin Kernel Version 16.1.0: Thu Oct 13 21:26:57 PDT 2016; root:xnu-3789.21.3~60/RELEASE_X86_64 x86_64

A DESCRIPTION OF THE PROBLEM :
I am living in Hanoi, Vietnam.
----------------------------------------------------------------------------------------------
package oop;

import java.text.NumberFormat;
import java.util.Locale;

public class CurrencyPrinter {

    public static void main(String[] args) {
        double amount = 1234567.8901234;
        NumberFormat nf = NumberFormat.getCurrencyInstance();
        System.out.println(nf.format(amount));
        System.out.println();

        nf = NumberFormat.getCurrencyInstance(Locale.FRANCE);
        System.out.println(nf.format(amount));
        System.out.println();

        System.out.println(nf.getClass().getName());
    }

}

-------------------------------------------------------------------------------
Result:

VND1,234,568

1 234 567,89 €

java.text.DecimalFormat
-------------------------------------------------------------------------------


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
1.234.568 VND


(In Vietnam, 3-digits group separator is dot character)
ACTUAL -
VND1,234,568

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
package oop;

import java.text.NumberFormat;
import java.util.Locale;

public class CurrencyPrinter {

    public static void main(String[] args) {
        double amount = 1234567.8901234;
        NumberFormat nf = NumberFormat.getCurrencyInstance();
        System.out.println(nf.format(amount));
        System.out.println();

        nf = NumberFormat.getCurrencyInstance(Locale.FRANCE);
        System.out.println(nf.format(amount));
        System.out.println();

        System.out.println(nf.getClass().getName());
    }

}
---------- END SOURCE ----------