jstl条件不起作用

Question

I can't understand how is that possible, so i will just show the code.

This works. As expected, a list of "PAIR" is printed:

<c:forEach var="element" items="${list}">
<c:choose>
    <c:when test="true">
       <div>PAIR ${element}</div>
    </c:when>
    <c:otherwise>
       <div>ODD ${element}</div>
    </c:otherwise>
</c:choose>
</c:forEach>

This doesn't work. Print only "ODD":

<c:forEach var="element" items="${list}">
<c:choose>
    <c:when test="true == true">
       <div>PAIR ${element}</div>
    </c:when>
    <c:otherwise>
       <div>ODD ${element}</div>
    </c:otherwise>
</c:choose>
</c:forEach>

Someone can help me?

Answer 1

You are missing the EL literal: ${..} . Use test="${true == true}" and it will work.

The first example works because the string true , when converted to boolean, is true . The parser tries to convert the string-value you passed to boolean using Boolean.valueOf(..) . And a conversion of the true == true string, using Boolean.valueOf(..) gives you false .