java - 如何从货币代码中获取 NumberFormat 实例？

Question

如何获取与 ISO 4217 货币代码(例如“EUR”或“USD”)对应的 NumberFormat(或 DecimalFormat)实例以便格式化价格正确吗？

Note 1: The problem I'm having is that the NumberFormat/DecimalFormat classes have a getCurrencyInstance(Locale locale) method but I can't figure out how to get to a Locale object from an ISO 4217 currency code.

Note 2: There is also a java.util.Currency class which has a getInstance(String currencyCode) method (returning the Currency instance for a given ISO 4217 currency code) but again I can't figure out how to get from a Currency object to a NumberFormat instance...

Answer 1

我不确定我是否理解正确，但您可以尝试类似的方法:

public class CurrencyTest
{
    @Test
    public void testGetNumberFormatForCurrencyCode()
    {
        NumberFormat format = NumberFormat.getInstance();
        format.setMaximumFractionDigits(2);
        Currency currency = Currency.getInstance("USD");
        format.setCurrency(currency);

        System.out.println(format.format(1234.23434));
    }   
}

输出:

1,234.23

请注意，我分别设置了小数位数的最大值，NumberFormat.setCurrency不触及最大小数位数:

Sets the currency used by this number format when formatting currency values. This does not update the minimum or maximum number of fraction digits used by the number format.