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I have Tomcat 3.1 set up on a Windows2000 machine. Let's say I have two jsp pages... file A: "/test.jsp" file B: "/my_folder/test.jsp" ...both "test.jsp", files A and B, are identical. Both files contain: "<jsp:useBean id="me" class="myclass" scope="page" />" the folder "/WEB-INF/classes" contains myclass.class When I try my web browser on file A then everything works fine (thru the web server on localhost, of course). However, I go into file B, then I get this error: <the file's directory> "Class my_folder.myclass not found." so, my question is...how can I get "myclass" to properly work in all directories of the web site? Any help would be greatly appreciated. Thanks in advance. -Ben [ November 23, 2002: Message edited by: Ben Sch ]
How so? I am new to Tomcat administration, so I'm not familiar with a "default package." Would you suggest that I modify some .xml file to make the class visible to all pages?
It's not a Tomcat thing at all, but a Java thing. When you don't use a package declaration in your class it is placed in a "default package". To use an explicit package, place a package declaration at the beginning of your class. For example:
It's a very good idea to place all your classes in a well-orgranized package structure rather than letting them all pile up in the default package. This may solve your problem in that package-less classes seem to confuse some web containers. hth, bear
Joined: Nov 23, 2002
Thank you for the response, but the problem remains. I have put all my classes into a package. I then tried putting the package into the "/WEB-INF/classes" folder, tried a "/WEB-INF/lib", and even tried "<tomcat dir>/lib/common". None of these made the package visible to the JSPEngine. Since my JSP pages are loading correctly, and the initial javabean class is properly loaded into a page, I suspect that I have tomcat mostly configured. Although, I am still unable to have classes included in pages that are not in the root directy. Do you suppose I need to modify some .xml file or maybe add an environment variable (classpath, etc.) of some sort? [ November 24, 2002: Message edited by: Ben Sch ] [ November 24, 2002: Message edited by: Ben Sch ]
hi ben i think u can add the classpath in one of the configuration files for tomcat i cannot remember the name of the file offhand but if u go thru the conf files u may come across a entry for the classpath for the server. The solution for u'r problem is what Bear had suggested as i too had faced a similar problem in the past. i will try to get my hands on a tomcat server rightaway and get back with the exact file in which the entry needs to be done if u r unable to find it.
There is no need to muck with the Tomcat classpath -- in fact doing so is liable to cause more problems than it would solve. Why not describe how you are setting up your classpath unders WEB-INF classes? If your bean is resident in the correct classpath hierarchy under WEB-INF/classes there is no reason on earth that your JSPs should be unable to see them. No Tomcat configuration mucking about should be required. bear
Joined: Nov 23, 2002
Please let me know if this information helps figure out the problem. It strikes me that Tomcat knows that there is a web application that I want to run, and that there are some java classes/packages that I wish to use. It just seems that the page that tries to load the
Here is how I'm trying to load it: --------------------------------- <jsp:useBean id="mytable" class="MyTableClass" scope="page" />
Here is a list of my environment variables that relate to Tomcat: ---------------- CATALINA_HOME C:\jakarta-tomcat-3.3.1 CLASSPATH C:\j2sdk1.4.0_02\lib\comm.jar;C:\jakarta-tomcat-3.3.1\bin;C:\jakarta-tomcat-3.3.1\lib\common; C:\jakarta-tomcat-3.3.1\webapps\ROOT\WEB-INF\classes\ JAVA_HOME C:\j2sdk1.4.0_02 PATH C:\j2sdk1.4.0_02\bin;C:\jakarta-tomcat-3.3.1\bin;C:\jakarta-tomcat-3.3.1\webapps; to describe again the funny behavior: ------------------ the page itself could be called xyz.jsp when I try loading the class at /xyz.jsp everything works fine when I try loading the class at /mydir/xyz.jsp I then get the funny error that says "Class mydir.MyTableClass not found." Thanks for any help. -Ben [ November 25, 2002: Message edited by: Ben Sch ] [ November 25, 2002: Message edited by: Ben Sch ]
Rajesh is correct: you must specify the fully-qualified path name of the class. Otherwise, how does Java know where to look for it? Scenario: The bean class named MyBean is defined in package com.bensch.beans. In your java file you will need:
Your java file will be named MyBean.java and will reside in a folder relative to the root of you project as such (assume Windows):
When you compile you will do so from c:\projectroot. In your web app, the class file should end up in
And finally, your useBean directive will contain
Notice how the package hierarchy is carried throughout the process. hth, bear [ November 26, 2002: Message edited by: Bear Bibeault ]