If you take advantage of Struts 2 i18n support you can get a very elegant solution as follows.
I can define the following property, that takes advantage of Java's MessageFormat support in properties files ResourceBundles.
item.price={0,number,currency}
Now, I will pull this text resource from my bundle with the struts 2 text tag, passing a parameter that references some data I've prepared in my action.
<s:text name="item.price">
<s

aram value="totalCost"/>
</s:text>
The output will be a currencty formatted price.
Is this what you had in mind?