Accessing Request object from custom JSP tags

Posted by Byron on Stack Overflow See other posts from Stack Overflow or by Byron
Published on 2010-06-01T21:59:37Z Indexed on 2010/06/01 22:23 UTC
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I'm trying to make a set of custom tags that encapsulate form elements (markup and validation).

There's a method given to retrieve the "Out" object easily:

JspWriter out = getJspContext().getOut();

However I can't figure out how to get the request object. I want to be able to directly access the submitted form values from within the Tag class so that I can validate each field.

The documentation is quite sparse, so I thought maybe I could use the JspContext object to somehow get the request attributes. But I don't understand the different scopes.

System.out.println(getJspContext().findAttribute("field1"));

always prints "null".

Enumeration e = getJspContext().getAttributeNamesInScope(1);

Looping through and printing out the enumeration just gives me a list of classes that don't exist:

javax.servlet.jsp.jspOut
javax.servlet.jsp.jspPage
javax.servlet.jsp.jspSession
javax.servlet.jsp.jspApplication
javax.servlet.jsp.jspPageContext
javax.servlet.jsp.jspConfig
javax.servlet.jsp.jspResponse
javax.servlet.jsp.jspRequest

So is this even possible?

If not, could anyone point me to a tag library that deals with form display and validation? I searched the internet for a couple hours and it seemed every single one was discontinued and I couldn't download them. Either that or suggest a better alternative for handling forms.

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