RE: [3.2] JSP Compiling Classpath issues -- finding WEB-INF/classes
Guys, I've copied in an email returned to a support desk regarding a problem similar to this. There is a link to mikal.org that explains it in better detail, but essentially it refers to where your classes are found, as to what classloader they inherit. And the solution we found (similar to the post) is to ensure your classpath is unset before starting Tomcat. Regards, Andrew Mc.Ghee Thanks again for your help on this, Looks like we have tracked down the problem, and it was due to a reference to the Poet SDK on the CLASSPATH. References to Poet code was finding the class instance on the jar file specified within the CLASSPATH itself, and so was not having access to the classloader from tomcat, making anything within webapps/WEB-INF/lib unavailable. We have simply removed the reference to the poet jar files from the classpath, and placed the jar file within the webapps/WEB-INF/lib directory, and voila! (No need to set the database classloader now either) Thanks again for your assistance in this, pointing out the classpath loading help to isolate the problem. A useful link regarding this problem was; http://mikal.org/interests/java/tomcat/archive/view?mesg=22444 (And probably explains the situation far better than I can) -Original Message- -Original Message- From: David Rees [mailto:[EMAIL PROTECTED]] Sent: 19 July 2001 22:27 To: [EMAIL PROTECTED] Subject: Re: [3.2] JSP Compiling Classpath issues -- finding WEB-INF/classes (Sorry about the double-qoute, I missed the original message) -Original Message- From: Will England [mailto:[EMAIL PROTECTED]] Sent: Thursday, July 19, 2001 10:49 AM To: [EMAIL PROTECTED] Subject: [3.2] JSP Compiling Classpath issues -- finding WEB-INF/classes Greetings! Over on tomcat-users, theres been a discussion on JSP's finding the WEB-INF/classes directory when compiling. They can't. From searches, I understand this issue has come up before in regards to the Coocon project. The root problem is that Jasper cannot find classes located in WEB-INF/classes of the web application that the JSP's belong to. This occurs when a JSP is either first deployed or the TOMCAT_HOME/work directory is cleared, requiring a recompile of the JSP's. The system is Tomcat 3.2 under Apache with mod_jk, running on SunOS 2.7 with JDK 1.2. I have noticed the same problem while doing some development using Tomcat 3.2.[23]. I worked around it by making sure that I unset the classpath before calling startup.sh, then things seemed to work properly and classes were found as expected. It seems that certain combinations of classes in different ares (CLASSPATH, WEB-INF/lib, or other) will break things, but I haven't pinned it down, so it could simply be user stupidity. -Dave
Re: [3.2] JSP Compiling Classpath issues -- finding WEB-INF/classes
On Thu, 19 Jul 2001, David Rees wrote: (Sorry about the double-qoute, I missed the original message) I have noticed the same problem while doing some development using Tomcat 3.2.[23]. I worked around it by making sure that I unset the classpath before calling startup.sh, then things seemed to work properly and classes were found as expected. Tried that. Tried hard-coding the classpath. If the web applications WEB-INF/classes directory was in the system classpath, it compiles. If it is not in the system classpath, the JSP's do not compile. So, why does Jasper not know about the web-application classpath? Will
RE: [3.2] JSP Compiling Classpath issues -- finding WEB-INF/classes
On Fri, 20 Jul 2001, Andrew McGhee wrote: Guys, I've copied in an email returned to a support desk regarding a problem similar to this. There is a link to mikal.org that explains it in better detail, but essentially it refers to where your classes are found, as to what classloader they inherit. And the solution we found (similar to the post) is to ensure your classpath is unset before starting Tomcat. The solution posted (unset your classpath, cause there might be a class with the same name somewhere else) is fine for first year university students. Most likely, that *is* what causes their problems. grin But, I have set, unset, hard coded, soft coded and so on the classpath. In tomcat.sh, I have a hard-coded classpath pointing to the .jar files in TOMCAT_HOME/lib, and tools.jar. Nothing else. I try to hit a JSP for the first time, the compile fails. Jasper reports that it cannot find classes that are located in the web applications WEB-INF/classes directory. Theoretically, the adaptive classloader should know about WEB-INF/classes, and I thought Jaspter used the adaptive classloader. If I change the hard-coded classpath in tomcat.sh to point to the web applications WEB-INF/classes directory, so that the WEB-INF/classes folder is in the system classpath, Jasper can now find the classes and compilation continues normally. Can one of the developers detail out where Jasper looks for classes for compiling JSPs? Thanks for any tips or suggestions! Will
Re: [3.2] JSP Compiling Classpath issues -- finding WEB-INF/classes
Oops, That's right, you can read any file you want from WEB-INF/classes using getResource() (which is probably what you are doing) -- that is implemented correctly in AdaptiveClassLoader. If you want to find all resources of a specified name (for example, you have a properties file of the same name at the web-application level and the system level, and you want to concatenate values from both places together), the ClassLoader class provides a getResources() method. (This method in turn calls findResources which is supposed to be implemented in all subclasses of ClassLoader, but isn't for AdaptiveClassLoader) I'm glad to know that fixed it. David Will England wrote: On Fri, 20 Jul 2001, David Haraburda wrote: Have you tried using the Jdk12Interceptor? That fixed class loading problems for me. In your server.xml do: RequestInterceptor className=org.apache.tomcat.request.Jdk12Interceptor/ Got that, and it fixed the finding of my .conf files that I store in WEB-INF/classes. I can now read any text file I want from WEB-INF/classes from a servlet. Note this will only fix the loading of CLASSES... if you have resources in your WEB-INF/classes directory, such as .properties files, that the ClassLoader is supposed to pick up, this will not happen. I submitted a patch for this to the mailing list last night, but haven't heard anything from a developer/committer yet. Odd. Worked well for me. As soon as the admin gets the box back up, I'll drop you a copy of my server.xml and the code I use to read a text file. A good way to see what ClassLoader is being used is by sticking in a System.out.println( CL: + Thread.currentThread().getContextClassLoader().toString() ); If it says com.sun.misc.something (I forget the package name), you are using the System classloader... if it says AdaptiveClassLoader, you are using the Tomcat one which knows about stuff in the WEB-INF directory. Nice tip - I'll try that! Will
[3.2] JSP Compiling Classpath issues -- finding WEB-INF/classes
Greetings! Over on tomcat-users, theres been a discussion on JSP's finding the WEB-INF/classes directory when compiling. They can't. From searches, I understand this issue has come up before in regards to the Coocon project. The root problem is that Jasper cannot find classes located in WEB-INF/classes of the web application that the JSP's belong to. This occurs when a JSP is either first deployed or the TOMCAT_HOME/work directory is cleared, requiring a recompile of the JSP's. The system is Tomcat 3.2 under Apache with mod_jk, running on SunOS 2.7 with JDK 1.2. The code in question is coming from a production Tomcat 3.1 system. I cannot add the WEB-INF/classes directory to my classpath. This will break several other parts of the system. What is the problem with Jasper reading WEB-INF/classes? I understand the the Coocon users found some kind of workaround, but I have been unable to find it. Thank you for any pointers or tips! Will -- /~'find `funny quote`': Command not found; humor not installed. 1986 Concours 72,xxx 1982 Maxim 12,xxx (For Sale!) CDA #00046 Overland Park, KS [EMAIL PROTECTED] PCS: 316-371-FOAD http://will.mylanders.com/
RE: [3.2] JSP Compiling Classpath issues -- finding WEB-INF/classes
I guess I don't follow, cuz I use this functionality of Tomcat every single day. Whether or not its under Apache shouldn't matter. - r -Original Message- From: Will England [mailto:[EMAIL PROTECTED]] Sent: Thursday, July 19, 2001 10:49 AM To: [EMAIL PROTECTED] Subject: [3.2] JSP Compiling Classpath issues -- finding WEB-INF/classes Greetings! Over on tomcat-users, theres been a discussion on JSP's finding the WEB-INF/classes directory when compiling. They can't. From searches, I understand this issue has come up before in regards to the Coocon project. The root problem is that Jasper cannot find classes located in WEB-INF/classes of the web application that the JSP's belong to. This occurs when a JSP is either first deployed or the TOMCAT_HOME/work directory is cleared, requiring a recompile of the JSP's. The system is Tomcat 3.2 under Apache with mod_jk, running on SunOS 2.7 with JDK 1.2. The code in question is coming from a production Tomcat 3.1 system. I cannot add the WEB-INF/classes directory to my classpath. This will break several other parts of the system. What is the problem with Jasper reading WEB-INF/classes? I understand the the Coocon users found some kind of workaround, but I have been unable to find it. Thank you for any pointers or tips! Will -- /~'find `funny quote`': Command not found; humor not installed. 1986 Concours 72,xxx 1982 Maxim 12,xxx (For Sale!) CDA #00046 Overland Park, KS [EMAIL PROTECTED] PCS: 316-371-FOAD http://will.mylanders.com/
Re: [3.2] JSP Compiling Classpath issues -- finding WEB-INF/classes
(Sorry about the double-qoute, I missed the original message) -Original Message- From: Will England [mailto:[EMAIL PROTECTED]] Sent: Thursday, July 19, 2001 10:49 AM To: [EMAIL PROTECTED] Subject: [3.2] JSP Compiling Classpath issues -- finding WEB-INF/classes Greetings! Over on tomcat-users, theres been a discussion on JSP's finding the WEB-INF/classes directory when compiling. They can't. From searches, I understand this issue has come up before in regards to the Coocon project. The root problem is that Jasper cannot find classes located in WEB-INF/classes of the web application that the JSP's belong to. This occurs when a JSP is either first deployed or the TOMCAT_HOME/work directory is cleared, requiring a recompile of the JSP's. The system is Tomcat 3.2 under Apache with mod_jk, running on SunOS 2.7 with JDK 1.2. I have noticed the same problem while doing some development using Tomcat 3.2.[23]. I worked around it by making sure that I unset the classpath before calling startup.sh, then things seemed to work properly and classes were found as expected. It seems that certain combinations of classes in different ares (CLASSPATH, WEB-INF/lib, or other) will break things, but I haven't pinned it down, so it could simply be user stupidity. -Dave
