Custom Tag not evaluating expression in attribute

Question

I have a custom tag that needs to take dynamic values in the attributes, but I can't seem to get the values "interpreted" correctly. I have the <rtexprvalue> tag set to "true" in my .tld file, which I thought was the only thing that was needed in order to accomplish what I am trying to do. However, that does not seem to be the case.
I am using WebLogic (8.1.4) and their <netui> tags, along with JSTL tags (1.0).
An example of what my code looks like is the following:
<test:myTag id="1" idx="<netui:content value='{container.index}' />">
    <netui:select ... />
</test:myTag>and
<c:set var="myIdx" value="<netui:content value='{container.index}' />" />
<test:myTag id="1" idx="<c:out value='${myIdx}' />">
    <netui:select ... />
</test:myTag>Neither of the above approaches has worked. In my code for my Tag.java file, I get the literal string values of <netui:content value='{container.index}' /> and <c:out value='${myIdx}' />, respectively, in my idx property.
Can someone give me any hints as to what I may be doing wrong?
Thanks.

Answer 1

Shouldnt that be
<netui:content value='${container.index}' />Actually, weblogic does not use the '$' prefix before
their expressions. Fine. Which in turn means weblogic has some custom expression evaluator.
Note weblogic 8.1
as a container doesnt implicitly supportexpressions
and you have to build in that feature into yourtag
library.Are you referring to the 'isELIgnored' attribute when
you mentioned the above statement? If not, can you
explain what you meant by "build that feature into
your tag library"?
It's like this - expression language is supported by default in all containers that implement the j2ee 1.4 spec (servlet 2.4/jsp 2.0). Additionally you should also declare your web application to adhere to the 2.4 standards (through the schema definition in web.xml). In applications that refer to the 2.3 dtd but are run on a 2.4 compliant container you can set the 'isELIgnored' attribute to false and use EL. This works because your container anyways supports it.
If your container doesnt provide support for EL (outside the jstl tags) as is the case with weblogic 8.1, then you can still use expressions by using something like the [url http://jakarta.apache.org/commons/el/]apache common evaluator  package. The difference being that you will have to call the evaluator classes to evaluate the attribute.
Are there any alternatives that I could use to
accomplish what I am trying to do?Did the above answer your question?
ram.