I can pass a variable from a JSP scriptlet to JSTL but not from JSTL to a JSP scriptlet without an error

Question

The following code causes an error:

 
 <%
   String resp = \"abc\";
   resp = resp + test;
   pageContext.setAt         


        

Answer 1

Scripts are raw java embedded in the page code, and if you declare variables in your scripts, then they become local variables embedded in the page.

In contrast, JSTL works entirely with scoped attributes, either at page, request or session scope. You need to rework your scriptlet to fish test out as an attribute:

<%
  String resp = "abc";
  String test = pageContext.getAttribute("test");
  resp = resp + test;
  pageContext.setAttribute("resp", resp);
%>

If you look at the docs for , you'll see you can specify scope as page, request or session, and it defaults to page.

Better yet, don't use scriptlets at all: they make the baby jesus cry.