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javaroundingbigdecimal

Why doesn't BigDecimal.stripTrailingZeros() remove always all trailing zeros?

I do the following

    MathContext context = new MathContext(7, RoundingMode.HALF_UP);
    BigDecimal roundedValue = new BigDecimal(value, context);

    // Limit decimal places
    try {
        roundedValue = roundedValue.setScale(decimalPlaces, RoundingMode.HALF_UP);
    } catch (NegativeArraySizeException e) {
        throw new IllegalArgumentException("Invalid count of decimal places.");
    }
    roundedValue = roundedValue.stripTrailingZeros();

    String returnValue = roundedValue.toPlainString();

In case the input is now "-0.000987654321" (= value) I get back "-0.001" (= return Value) which is ok.

In case the input is now "-0.0000987654321" I get back "-0.0001" which is also ok.

But when the input is now "-0.00000987654321" I get back "0.0000" instead of "0" which is not ok. What is wrong here? Why aren't the trailing zeros removed in this case?

Solution 
  • BigDecimal d = new BigDecimal("0.0000");
System.out.println(d.stripTrailingZeros());

    prints 0.0000 with Java 7 but 0 with Java 8. This is apparently a bug that has been fixed in Java 8.