null in headless client

I am using this in a jsp-page

<td>unitprice</td><td><input type="text" name="unitprice" value="<%=servoy_hc.getDataProviderValue(null,"unitprice")%>"></td>

when the unitprice is not filled in yet, I get an annoying: null
in this field.

How can I prevent this? I want that the fields become empty, instead of showing: null

Unlike with javascript you really have to check for a null value ```
value != null

Can you give me an complete example how to to this in jsp?
I can’t get it to work!