DecimalFormat pattern for BigDecimal.

Question

What pattern of DecimalFormat should I use so that when I format BigDecimals like

new BigDecimal("4235886589.00000");
new BigDecimal("4235886589.0000030000");
new BigDecimal("4235886589.0");
new BigDecimal("4235886589");

The output must have the following appearance:

4,235,886,589.00000;  4,235,886,589.0000030000; 4,235,886,589.0; 4,235,886,589;

So basically I'm trying to write a pattern which won't cut off zeros in the end and won't put them if they are not necessary. I tried to handle it with patterns:

DecimalFormat formatter = new DecimalFormat("#,###,##0.########");
DecimalFormat formatter = new DecimalFormat("#,###,##0.000000");

But the first formatter cuts off zeros, whereas the second one puts them where they are unnecessary.

Answer 1

I don't think you can do it in a straight way using the formatter. What you can do is wrap your Decimal in a class where you can store the appropriate format string computed at instantiation:

class MyBigDecimal {
  String asString;
  BigDecimal n;

  public MyBigDecimal(String asString) {
    this.asString = asString;
    n = new BigDecimal(asString);
  }
}