This JSP code was not outputting the properly formatted amount.

<dspel:valueof value="${dollars}" converter="currency" />

I tried forcing it by specifying the conversion parameters.

<dspel:valueof value="${dollars}" converter="currency" locale="en-CA" format="#.00" currency="$" />

I then debugged atg.droplet.CurrencyTagConverter using Eclipse and found this code being executed.

public String convertObjectToString(DynamoHttpServletRequest pRequest,
                                 Object pValue, Properties pAttributes)
  throws TagConversionException
{
  if ((pValue == null) || (pValue instanceof String))
    return (String)pValue;

It turns out pValue was a String which is why it was never being formatted.  But why is it a String?

Well the code that sets dollars looks like this.

<dspel:tomap var="paymentGroup" param="commerceItem.paymentGroups[1]" />
<c:set var="dollars" value="0" />
<c:if test="${not empty paymentGroup}">
  <c:set var="dollars" value="${paymentGroup.amount}" />
</c:if>

Apparently c:set converts the Double to a String.

To work around this problem I did this.

$<dspel:valueof number="0.00" value="${dollars}" />

For further reading please see Tag Converters in the ATG Page Developer’s Guide.