JSP expression language and dynamic attribute names

Question

I\'m trying to do something that seems like it should be relatively straightforward and running into a bit of a wall.

Let\'s say I\'ve got a list of products which

Answer 1

You can by using implicit objects:

There are objects that allow access to the various scoped variables described in Using Scope Objects.

• pageScope: Maps page-scoped variable names to their values
• requestScope: Maps request-scoped variable names to their values
• sessionScope: Maps session-scoped variable names to their values
• applicationScope: Maps application-scoped variable names to their values

When an expression references one of these objects by name, the appropriate object is returned instead of the corresponding attribute. For example, ${pageContext} returns the PageContext object, even if there is an existing pageContext attribute containing some other value.

So, for example:

<c:set var="selectedProductAttrName" value="selectedProduct_${product.id}"/>
${requestScope[selectedProductAttrName]}