5 Replies Latest reply on Feb 25, 2002 11:23 AM by John Twomey

    JSP does not refresh when deployed

    Kip Obenauf Newbie

      I've asked about this before, but I still haven't gotten it to work. I'd really appreciate any ideas.

      Most of the time when I make changes to a JSP and deploy, the changes do not show up in my JSP. Even if I restart JBoss, the old page gets served. For some reason though, maybe every 10th time or so, when I deploy, it works.

      I'm running JBoss-2.4.4_Tomcat-4.0.1. I have Apache using mod_jk to send JSP connections to JBoss via ajp13.

      I've tried deploying my war with a jboss-web.xml like this:

      <web-uri>myjsps.war</web-uri>
      <context-root>/myjsps</context-root>
      true


      I've tried modifying the jboss.jcml with like this:





      true


      I also tried adding a DefaultContext to as an attribute above:


      Any guidance would be much appreciated!

        • 1. Re: JSP does not refresh when deployed
          Sam Terrell Newbie

          I'm still new, but maybe this will help you... Tomcat/Catalina will extract the war file as soon as it starts or the war is deployed. From there on out, it locks the files that it is using and you can't regain access to those again until you tell Tomcat to do something else. If you look on the Jakarta pages under Tomcat, you'll find some useful manager commands (http://localhost:8080/manager/redeploy?path=/cheesy-war-that-wont-die might be the one you are looking for.) I'm very lazy and I am running my own private developemental server, so I just kill the server rm -rf (rd /q /s for windows) the directory in my script to build and deploy. After it is done, it will restart the Tomcat server. (I run mine independantly.)

          A more elegant and correct way can be found here: http://jakarta.apache.org/tomcat/tomcat-4.0-doc/manager-howto.html

          • 2. Re: JSP does not refresh when deployed
            John Twomey Newbie


            This may solve your problem. But the issue will be getting the Tomcat manager working with the integrated JBoss/Tomcat 4.01.

            Someone I know is having this same problem on an older machine running Linux.


            Has anyone been able to get the Tomcat Manager working with this INTEGRATED JBoss/Tomcat version and if so how?

            Thanks

            • 3. Re: JSP does not refresh when deployed
              Kip Obenauf Newbie

              I think I solved the problem. When you drop a war into /deploy, JBoss unpacks it into /tmp/deploy/Default/. This is important: the files in that folder have the datetimestamp that they had on the machine where you created the war file.

              JBoss then compiles the jsp file into a java and class file in /work/localhost/. This newly compiled file has the datetimestamp of the server.

              Apparently, JBoss compares the datetimestamp of the existing compiled files to the datetimestamp of the new files in /tmp/deploy/Default/. If the new files have a newer datetimestamp, it recompiles; otherwise it doesn't.

              In my case, the clock on my workstation was a few minutes slower than my server's clock. Therefore, if I quickly made changes and deployed again, the datetimestamp of the compiled file from the previous deploy was still newer than the datetimestamp of the new files. Result: the compiled files were not getting updated, and my changes were not appearing in the browser.

              I worked around this by setting the time on my workstation a couple minutes ahead of my server.

              This looks like a design flaw to me. Comparing datetimestamps is not a good way to see if a file has changed. The JBoss loader/compiler should compare a hash of the file's contents instead, or something similar.

              • 4. Re: JSP does not refresh when deployed
                Adrian Brock Master

                If you are interested have a look at
                org.apache.jasper.compiler.JSPCompiler.isOutDated()

                Here it checks the generated class file against the
                JSP file.

                Tomcat/catalina correctly spots the source JSP has
                changed (using timestamps), but the compiler ignores the
                redeployment request.

                In fact, potentially it is checking the timestamp on
                a remote machine against one on the local machine, the
                source can be specified by any URL.

                I've got an open bug about this with apache for a
                different reason.
                If the source URL is a "file:", it doesn't work.
                Sun's file url protocol handler always returns zero
                for lastModified().
                It only works with Tomcat because they use LDAP
                to access directories.

                Regards,
                Adrian

                • 5. Re: JSP does not refresh when deployed
                  John Twomey Newbie

                  Awesome work kobenauf, I will pass on the work-around.

                  Thanks,
                  JT