this is a similar thread - see if helps at all: http://marc.theaimsgroup.com/?l=tomcat-user&w=2&r=1&s=filters+running+twice&; q=b
Charlie > -----Original Message----- > From: Cédric Viaud [mailto:[EMAIL PROTECTED]] > Sent: Wednesday, November 27, 2002 8:31 AM > To: Tomcat Users List > Subject: Re: Pb with HEAD request > > > Hi Kristján, > > in fact, i've first check the RFC of HTTP 1.1 (see after the > mail what it > says about HEAD command). So i've look to the servlet > specification .And > haven't seen the "doHead" method. > > Next to your reply , i've checked again, and discover that i > MISSED it :-( > > So i've coded the "doHead" method , but it never seems to be > called by my > servlet. I can't manage to know if this is a client or a server issue. > > Anyone gets an idea. ? > > Anynyway, i think i will have to implement a cache , because > some of my Get > actions need many calculation, and doing this twice for the > same request > will decrease the application performance. > > Thanks for help, regards, > > Cédric > > > -------------------------------------------------------------- > -------------- > ---- > From RFC 2616 about HTTP 1.1 > > "9.4 HEAD > The HEAD method is identical to GET except that the server > MUST NOT return a > message-body in the response. The > metainformation contained in the HTTP headers in response to > a HEAD request > SHOULD be identical to the > information sent in response to a GET request. This method > can be used for > obtaining metainformation about the > entity implied by the request without transferring the > entity-body itself. > This method is often used for testing > hypertext links for validity, accessibility, and recent modification. > The response to a HEAD request MAY be cacheable in the sense that the > information contained in the response MAY > be used to update a previously cached entity from that > resource. If the new > field values indicate that the cached entity > differs from the current entity (as would be indicated by a change in > Content-Length, Content-MD5, ETag > or Last-Modified), then the cache MUST treat the cache entry > as stale." > > > > ----- Original Message ----- > From: "Kristján Bjarni Guđmundsson" <[EMAIL PROTECTED]> > To: "Tomcat Users List" <[EMAIL PROTECTED]> > Sent: Tuesday, November 26, 2002 4:40 PM > Subject: Re: Pb with HEAD request > > > You really should look into the servlet specification. > I think if you override doHead for your servlet > > doHead(HttpServletRequest req, HttpServletResponse resp) > > Receives an HTTP HEAD request from the protected service method and > handles the request. > > Default action for doHead is to simply call doGet > > Cédric Viaud <[EMAIL PROTECTED]> wrote on > 26.11.2002 15:32:45: > > > Hi, > > > I have Tomcat server 4.0.4 on NT 4 that contains a servlets in > > charge to create SVG content. > > > The client is Internet Explorer 5.5. It loads the following > simple HTML > page : > > > <html> > > <body> > > <embed width="200" height="200" > src="http://localhost:8080/myContext/MyServlet > > > > > </body> > > </html> > > > The problem is that my servlet is invoked twice. > > > My supposition is that IE is sending a HEAD (or GET) request to know > > the content type of the URL and then run the Adobe SVG plugin. When > > started the plugin connects also the servlet to get SVG content. > > HTTP spec says that HEAD request must return the same headers as GET > > request. What is sure is that my code is executed twice, not only > > the part that concerns response headers. But how can I do to know > > with the servlet if the request is a GET or a HEAD. I test the > > HttpRequest.getMethod() but it always return "GET". > > > Does someone know how to "configure" tomcat or anything else to > > avoid the two executions ? > > > Thanks. > > > > > > -- > To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]> -- To unsubscribe, e-mail: <mailto:[EMAIL PROTECTED]> For additional commands, e-mail: <mailto:[EMAIL PROTECTED]>
