Removing trailing zeros from BigDecimal in Java

bigdecimal, java

Solution

Use `toPlainString()`

BigDecimal d = new BigDecimal("600.0").setScale(2, RoundingMode.HALF_UP).stripTrailingZeros();
System.out.println(d.toPlainString()); // Printed 600 for me

I'm not into JSF (yet), but converter might look like this:

@FacesConverter("bigDecimalPlainDisplay")
public class BigDecimalDisplayConverter implements Converter {
    @Override
    public Object getAsObject(FacesContext context, UIComponent component, String value) {
        throw new BigDecimal(value);
    }

    @Override
    public String getAsString(FacesContext context, UIComponent component, Object value) {
        BigDecimal  bd = (BigDecimal)value;
        return bd.setScale(2, RoundingMode.HALF_UP).stripTrailingZeros().toPlainString();
    }
}

and then in xhtml:

<h:inputText id="bigDecimalView" value="#{bigDecimalObject}" 
    size="20" required="true" label="Value">
    <f:converter converterId="bigDecimalPlainDisplay" />
</h:inputText>

Problem

I need to remove trailing zeros from `BigDecimal` along with `RoundingMode.HALF_UP`. For instance, ``` Value Output 15.3456 <=> 15.35 15.999 <=> 16 //No trailing zeros. 15.99 <=> 15.99 15.0051 <=> 15.01 15.0001 <=> 15 //No trailing zeros. 15.000000<=> 15 //No trailing zeros. 15.00 <=> 15 //No trailing zeros. ``` `stripTrailingZeros()` works but it returns scientific notations in situations like, ``` new BigDecimal("600.0").setScale(2, RoundingMode.HALF_UP).stripTrailingZeros(); ``` In this case, it returns `6E+2`. I need this in a custom converter in JSF where it might be ugly for end users. So, what is the proper way of doing this?

Original source