Re: [Resin-interest] Resin 4.0.5 Buffer Commit Point
The 'problem' is that you are processing your data in your view controller JSP which is not really where it belongs. You should just move that code up a layer into Java. The t:action comes from using http://tagonist.tigris.org/. Tagonist (or something like it that allows you to execute java code as an 'action') is very easy to integrate into your app and will solve the problem without relying on esoteric (and brittle) buffer sizes. jon So the code example, from a style stand-point, is almost spot on with how > have laid our model/view/controller JSPs. I don't know what a t: library, > is but I am sure its some custom way to call your model code. We do a > instead, but it's stylistically the same -- the model is > separated from your example controller. > > In a JSP-based controller we are parsing the results of the model data into > a hashmap and then processing the elements in the hashmap to determine if we > need to redirect before we call the view. So our controller looks like: > > > > <%-- Process the results of the model --%> > > > > > > > > > > > > > > So I am not quite tracking with you on what we need to differently in our > controller? We are trying to do a redirect before we get to the view layer, > as you suggest, and as your code is suggesting. > > Right or wrong, this is a style we have used in several places, and instead > of modifying a lot of code it would be much easier if we can simply change > the buffer size commit point. We definitely didn't intend to exploit a bug, > we are just trying to follow easy to maintain good MVC practices and ran > into this hiccup. > > Fortunately through all of our testing this is the only show stopper for us > from rolling out to the newest version of Resin 4.0.5 with our existing code > base. > > Thanks for you help, > > Aaron > > ___ > resin-interest mailing list > resin-interest@caucho.com > http://maillist.caucho.com/mailman/listinfo/resin-interest > > ___ resin-interest mailing list resin-interest@caucho.com http://maillist.caucho.com/mailman/listinfo/resin-interest
Re: [Resin-interest] Resin 4.0.5 Buffer Commit Point
On 3/25/2010 10:31 AM, Jon Stevens wrote: I don't mind using JSP's for some of the (separated) control logic. For example, you have a form action: Inside of it, it looks like this: http://code.google.com/p/subetha/source/browse/trunk/web/email_confirm_submit.jsp That said, look at that code. The logic for determining the next page to redirect to is either in the or within the JSTL within the email_confirm_submit.jsp. Generally, it is nice to have it in JSTL because a UI person can change the location of the final page without having to modify java code to do so. The point being that by the time you get to the view layer (ie: a jsp that doesn't have _submit.jsp at the end), you don't do a redirect. You are depending on what is effectively a bug in Resin that has now been fixed in a newer version. You should modify your code to change that dependency because you can (and should) be doing it differently. jon On Thu, Mar 25, 2010 at 8:18 AM, Aaron Freeman mailto:aaron.free...@layerz.com>> wrote: It's not in the view layer. We segregate our controller JSPs from our view JSPs. So you will change your argument to say that we should not use JSPs at the control layer, and of course _most_ of our control logic is in pure Java, but there are cases where having our controller logic written in JSTL (and separated from other model/view JSP pages) is a substantial advantage for us. So the question still stands, is there a global way to change the commit point so we don't have to constantly reset a connection to clear the buffer? Aaron On 3/25/2010 10:02 AM, Jon Stevens wrote: This is why you don't put application logic into the view layer. Before you 'push' your data into the view, figure out if you want to do the redirect or not. jon On Thu, Mar 25, 2010 at 7:49 AM, Aaron Freeman mailto:aaron.free...@layerz.com>> wrote: We take some fairly lengthy queries (lengthy row based on row count), and push the data into hashmaps in JSTL pages. After that sometimes we evaluate the hashmap and sometimes have to redirect the request to another page. In 3.0.23 it works with no problems. In 4.0.5 we get "java.lang.IllegalStateException: Can't sendRedirect() after data has committed to the client." The reason being, that the for loop is causing a ton of white space to be sent to be buffered up, and at some point a buffer size limit has been hit with only whitespace, causing Resin to then send the HTTP headers and commit the request. So in the for loop I can do this to "fix" the problem: <% response.reset(); %> The question is, is there a setting in the resin.xml where I can change the buffer size globally, or do we have to go to modify all JSPs that potentially have this problem? Was the default commit point changed between 3.0.x and 4.0.x, or some other architecture change, as we have never seen this until now?* * Thanks, Aaron* * So the code example, from a style stand-point, is almost spot on with how have laid our model/view/controller JSPs. I don't know what a t: library, is but I am sure its some custom way to call your model code. We do a instead, but it's stylistically the same -- the model is separated from your example controller. In a JSP-based controller we are parsing the results of the model data into a hashmap and then processing the elements in the hashmap to determine if we need to redirect before we call the view. So our controller looks like: <%-- Process the results of the model --%> So I am not quite tracking with you on what we need to differently in our controller? We are trying to do a redirect before we get to the view layer, as you suggest, and as your code is suggesting. Right or wrong, this is a style we have used in several places, and instead of modifying a lot of code it would be much easier if we can simply change the buffer size commit point. We definitely didn't intend to exploit a bug, we are just trying to follow easy to maintain good MVC practices and ran into this hiccup. Fortunately through all of our testing this is the only show stopper for us from rolling out to the newest version of Resin 4.0.5 with our existing code base. Thanks for you help, Aaron ___ resin-interest mailing list resin-interest@caucho.com http://maillist.caucho.com/mailman/listinfo/resin-interest
Re: [Resin-interest] Resin 4.0.5 Buffer Commit Point
I don't mind using JSP's for some of the (separated) control logic. For example, you have a form action: Inside of it, it looks like this: http://code.google.com/p/subetha/source/browse/trunk/web/email_confirm_submit.jsp That said, look at that code. The logic for determining the next page to redirect to is either in the or within the JSTL within the email_confirm_submit.jsp. Generally, it is nice to have it in JSTL because a UI person can change the location of the final page without having to modify java code to do so. The point being that by the time you get to the view layer (ie: a jsp that doesn't have _submit.jsp at the end), you don't do a redirect. You are depending on what is effectively a bug in Resin that has now been fixed in a newer version. You should modify your code to change that dependency because you can (and should) be doing it differently. jon On Thu, Mar 25, 2010 at 8:18 AM, Aaron Freeman wrote: > It's not in the view layer. We segregate our controller JSPs from our > view JSPs. So you will change your argument to say that we should not use > JSPs at the control layer, and of course _most_ of our control logic is in > pure Java, but there are cases where having our controller logic written in > JSTL (and separated from other model/view JSP pages) is a substantial > advantage for us. > > So the question still stands, is there a global way to change the commit > point so we don't have to constantly reset a connection to clear the buffer? > > Aaron > > > > On 3/25/2010 10:02 AM, Jon Stevens wrote: > > This is why you don't put application logic into the view layer. Before you > 'push' your data into the view, figure out if you want to do the redirect or > not. > > jon > > On Thu, Mar 25, 2010 at 7:49 AM, Aaron Freeman > wrote: > >> We take some fairly lengthy queries (lengthy row based on row count), and >> push the data into hashmaps in JSTL pages. After that sometimes we evaluate >> the hashmap and sometimes have to redirect the request to another page. In >> 3.0.23 it works with no problems. In 4.0.5 we get >> "java.lang.IllegalStateException: Can't sendRedirect() after data has >> committed to the client." >> >> The reason being, that the for loop is causing a ton of white space to be >> sent to be buffered up, and at some point a buffer size limit has been hit >> with only whitespace, causing Resin to then send the HTTP headers and commit >> the request. >> >> So in the for loop I can do this to "fix" the problem: >> >> > var="rewriteUrlsQuery"> >> <% response.reset(); %> >> >> >> >> The question is, is there a setting in the resin.xml where I can change >> the buffer size globally, or do we have to go to modify all JSPs that >> potentially have this problem? Was the default commit point changed between >> 3.0.x and >> 4.0.x, or some other architecture change, as we have never seen this until >> now?* >> * >> Thanks, >> >> Aaron* >> * >> >> > > ___ > resin-interest mailing list > resin-interest@caucho.com > http://maillist.caucho.com/mailman/listinfo/resin-interest > > ___ resin-interest mailing list resin-interest@caucho.com http://maillist.caucho.com/mailman/listinfo/resin-interest
Re: [Resin-interest] Resin 4.0.5 Buffer Commit Point
It's not in the view layer. We segregate our controller JSPs from our view JSPs. So you will change your argument to say that we should not use JSPs at the control layer, and of course _most_ of our control logic is in pure Java, but there are cases where having our controller logic written in JSTL (and separated from other model/view JSP pages) is a substantial advantage for us. So the question still stands, is there a global way to change the commit point so we don't have to constantly reset a connection to clear the buffer? Aaron On 3/25/2010 10:02 AM, Jon Stevens wrote: This is why you don't put application logic into the view layer. Before you 'push' your data into the view, figure out if you want to do the redirect or not. jon On Thu, Mar 25, 2010 at 7:49 AM, Aaron Freeman mailto:aaron.free...@layerz.com>> wrote: We take some fairly lengthy queries (lengthy row based on row count), and push the data into hashmaps in JSTL pages. After that sometimes we evaluate the hashmap and sometimes have to redirect the request to another page. In 3.0.23 it works with no problems. In 4.0.5 we get "java.lang.IllegalStateException: Can't sendRedirect() after data has committed to the client." The reason being, that the for loop is causing a ton of white space to be sent to be buffered up, and at some point a buffer size limit has been hit with only whitespace, causing Resin to then send the HTTP headers and commit the request. So in the for loop I can do this to "fix" the problem: <% response.reset(); %> The question is, is there a setting in the resin.xml where I can change the buffer size globally, or do we have to go to modify all JSPs that potentially have this problem? Was the default commit point changed between 3.0.x and 4.0.x, or some other architecture change, as we have never seen this until now?* * Thanks, Aaron* * ___ resin-interest mailing list resin-interest@caucho.com http://maillist.caucho.com/mailman/listinfo/resin-interest
Re: [Resin-interest] Resin 4.0.5 Buffer Commit Point
This is why you don't put application logic into the view layer. Before you 'push' your data into the view, figure out if you want to do the redirect or not. jon On Thu, Mar 25, 2010 at 7:49 AM, Aaron Freeman wrote: > We take some fairly lengthy queries (lengthy row based on row count), and > push the data into hashmaps in JSTL pages. After that sometimes we evaluate > the hashmap and sometimes have to redirect the request to another page. In > 3.0.23 it works with no problems. In 4.0.5 we get > "java.lang.IllegalStateException: Can't sendRedirect() after data has > committed to the client." > > The reason being, that the for loop is causing a ton of white space to be > sent to be buffered up, and at some point a buffer size limit has been hit > with only whitespace, causing Resin to then send the HTTP headers and commit > the request. > > So in the for loop I can do this to "fix" the problem: > > var="rewriteUrlsQuery"> > <% response.reset(); %> > > > > The question is, is there a setting in the resin.xml where I can change the > buffer size globally, or do we have to go to modify all JSPs that > potentially have this problem? Was the default commit point changed between > 3.0.x and > 4.0.x, or some other architecture change, as we have never seen this until > now?* > * > Thanks, > > Aaron* > * > > ___ > resin-interest mailing list > resin-interest@caucho.com > http://maillist.caucho.com/mailman/listinfo/resin-interest > > ___ resin-interest mailing list resin-interest@caucho.com http://maillist.caucho.com/mailman/listinfo/resin-interest
