How do i create a session using Dynamic Checkbox?

Question

Iam putting the value in an array and session that iam getting its always showing me null...

<%
                List<String> Cartlist=new ArrayList<String>();

                String[] cart=request.getParameterValues("item");
                if(cart!=null){
                for(int i=0; i<cart.length;i++){    
                out.println(cart[i]);
                Cartlist.add(cart[i]);
                }
        }
%>
            <%session.setAttribute("list",Cartlist);%>



 <%ArrayList<String> ca = (ArrayList<String>)session.getAttribute("List");

                   out.println(ca);
             %>

Answer 1

Use

 session.getAttribute("list");

instead of

 session.getAttribute("List");

Answer 2

Session attributes are case-sensitive.

Use

session.getAttribute("list")

Refer Case sensitivity in Session Attributes.

Suggestion: Using scriplets in JSPs is highly discouraged. How to avoid Java code in JSP files? says it all.

Answer 3

First use list instead List:

   session.getAttribute("list")

If you want to create a dynamic checkbox try to use jstl like this:

  <c:forEach var="item" items="${list}">
    ${item}  <input type="checkbox" name="${item}"  value="${item}"/>
  </c:forEach>