Question

I have the following code in my jsp scriptlet (inside <% %>):

boolean blockScreen = false;
    if(title.equalsIgnoreCase(labelA) || title.equalsIgnoreCase(labelB))
    {
    blockScreen = true;
    }

The java file generated corresponding to the above jsp contains following code(identical):

boolean blockScreen = false;
        if(title.equalsIgnoreCase(labelA) || title.equalsIgnoreCase(labelB))
        {
        blockScreen = true;
        }

But when I debug, I can not see the blockScreen variable. I decompiled the class file, and can see the following code:

   if(!title.equalsIgnoreCase(labelA))
            if(!title.equalsIgnoreCase(labelB));

Not sure why the blockScreen variable is getting cleaned out in the class file. The same variable is used further down in a c:choose tag:

<c:choose>
<c:when test="${blockScreen==true}">
<!--do something -->    
</c:when>
<c:otherwise>
<!--do something else -->
</c:otherwise>
</c:choose>

I am using JBoss EAP 6 server.

Any help in this regard appreciated.

Answer 1

EL expression ${blockScreen==true} uses a request attribute named blockScreen, not a scriptlet variable of the same name, therefore compiler is free to optimize away the usused variable.

If you want to use a scriptlet variable instead, try <c:when test="<%= blockScreen %>">.