Question

Is it possible to check if an attribute has been added to the model?

//in the controller teh variable is not always added
//
model.addAttribute("variable", myVariable);

and in the jsp something like this

<c:choose>
    <c:when test="${variable is present}">
        Not present
    </c:when>
    <c:otherwise>
        Present
    </c:otherwise>
</c:choose>

Thanks

Answer 1

JSTL/EL cannot check if an attribute has been added to the model. For that you need to implement an observer/observable yourself.

EL can however check if a bean property or a map value is not null or empty.

<c:when test="${not empty bean.property}">

---

<c:when test="${not empty map.key}">

See also:

• Java EE tutorial – Overview of EL operators
• Java EE tutorial – Examples of EL expressions