org.apache.tomcat.sendfile.support attribute returned via getAttribute() but name not returned via getAttributeNames()

Jun 5 (8 days ago)
Chris Markle to users

Hi,

Probably missing something simple here but I can't figure it out... I
have pretty much just modified a simpel hello world servlet as I start
to play around with NIO sendfile support. I am using Tomcat 6.0.20. I
am trying to check for the org.apache.tomcat.sendfile.support which
says I can use the sendfile mode. When I request the request
atttributes in the doPut method via getAttributeNames(), I seem to get
back an Enumeration with no attribute names in it. None... But when I
ask for the org.apache.tomcat.sendfile.support attribute specifically
via getAttribute(), I do get the attribute and it is correctly set to
Boolean true/false depending on whether I've configured NIO in
server.xml.

Here is my code:

protected void doGet(HttpServletRequest request, HttpServletResponse response) 
	throws ServletException, IOException 
{
	Enumeration<String> attrNames = request.getAttributeNames();
	if (attrNames == null) {
		System.out.println("getAttributeNames returned null");
	} else {
		System.out.println("attrNames: " + attrNames.toString());
	}

	System.out.println("printing any attrs...");
	while (attrNames.hasMoreElements()) {
		String attrName = attrNames.nextElement();
		System.out.println("attr: " + attrName);
	}

	Boolean val = (Boolean) request.getAttribute("org.apache.tomcat.sendfile.support");
	if (val != null) {
		System.out.println("org.apache.tomcat.sendfile.support attr found: value: " + val.toString());
	} else {
		System.out.println("org.apache.tomcat.sendfile.support attr not found");
	}

	response.getWriter().write("Hello, world!");
}

Thanks in advance for any help on this...

Chris

* * * 

Jun 8 (4 days ago)
Chris Markle to users
	
Folks,

Going to try this again since I got no reply to my first inquiry. I'd
like to log a bug report along the lines of "request getAttributeNames
method does not return all request attributes (e.g.,
org.apache.tomcat.sendfile.support)". Either that or this is a doc
issues somewhere. I know in the scheme of things this is not an
earth-shattering issue / bug, still it's apparently not working
correctly.

I would put this one of two ways, either:

1. The Tomcat HttpRequest getAttributeNames method has a bug and
doesn't return the attribute like org.apache.tomcat.sendfile.support
(even though I can access that attribute via the getAttribute method);
or

2. There's a doc error in the getAttributeNames doc where the cases
where it doesn't show all attribute names needs to be explained.

Thanks!

Chris

* * * 

Jun 9 (4 days ago)
Rainer Jung to Tomcat
	
On 08.06.2009 22:15, Chris Markle wrote:
> Folks,
>
> Going to try this again since I got no reply to my first inquiry. I'd
> like to log a bug report along the lines of "request getAttributeNames
> method does not return all request attributes (e.g.,
> org.apache.tomcat.sendfile.support)". Either that or this is a doc
> issues somewhere. I know in the scheme of things this is not an
> earth-shattering issue / bug, still it's apparently not working
> correctly.
>
> I would put this one of two ways, either:
>
> 1. The Tomcat HttpRequest getAttributeNames method has a bug and
> doesn't return the attribute like org.apache.tomcat.sendfile.support
> (even though I can access that attribute via the getAttribute method);
> or
>
> 2. There's a doc error in the getAttributeNames doc where the cases
> where it doesn't show all attribute names needs to be explained.
>
> My original message on the topic is below.

Yes, there are request attributes, that you can retrieve via
getAttribute(), but are not visible in getAttributeNames(). Those are
mostly somehow connector internal attributes, but yes, some of them can
be interesting to use in a webapp.

Unfortunately this will not be easy to fix, but you should add an issue
to Bugzilla.

Regards,

Rainer

* * * 
	
Chris Markle to Tomcat
	
Ranier,

> Yes, there are request attributes, that you can retrieve via
> getAttribute(), but are not visible in getAttributeNames(). Those are
> mostly somehow connector internal attributes, but yes, some of them can
> be interesting to use in a webapp. Unfortunately this will not be easy to
> fix, but you should add an issue to Bugzilla.

Thanks for the reply. I'll log something in Bugzilla per your request.

Chris