ologist`s story

package com.opensymphony.webwork.dispatcher;

import com.opensymphony.xwork.ActionContext;
import com.opensymphony.xwork.util.OgnlValueStack;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;

/**
* <!-- START SNIPPET: javadoc -->
*
* All WebWork requests are wrapped with this class, which provides simple JSTL accessibility. This is because JSTL
* works with request attributes, so this class delegates to the value stack except for a few cases where required to
* prevent infinite loops. Namely, we don't let any attribute name with "#" in it delegate out to the value stack, as it
* could potentially cause an infinite loop. For example, an infinite loop would take place if you called:
* request.getAttribute("#attr.foo").
*
* <!-- END SNIPPET: javadoc -->
*
* @since 2.2
*/
public class WebWorkRequestWrapper extends HttpServletRequestWrapper {
   public WebWorkRequestWrapper(HttpServletRequest req) {
       super(req);
   }

   public Object getAttribute(String s) {
       if (s != null && s.startsWith("javax.servlet")) {
           // don't bother with the standard javax.servlet attributes, we can short-circuit this
           // see WW-953 and the forums post linked in that issue for more info
           return super.getAttribute(s);
       }

       Object attribute = super.getAttribute(s);

       boolean alreadyIn = false;
       //WW-1365
       ActionContext ctx = ActionContext.getContext();
       Boolean b = (Boolean) ctx.get("__requestWrapper.getAttribute");
       if (b != null) {
           alreadyIn = b.booleanValue();
       }

       // note: we don't let # come through or else a request for
       // #attr.foo or #request.foo could cause an endless loop
       if (!alreadyIn && attribute == null && s.indexOf("#") == -1) {
           try {
               // If not found, then try the ValueStack
               ctx.put("__requestWrapper.getAttribute", Boolean.TRUE);
              OgnlValueStack stack = ctx.getValueStack();
               if (stack != null) {
                   attribute = stack.findValue(s);
               }
           } finally {
               ctx.put("__requestWrapper.getAttribute", Boolean.FALSE);
           }
       }
       return attribute;
   }
}