Picking up JAR files from JSP's

I have a web application with some JAR files that live under the WEB-INF/lib directory.
My understanding of webservers (Tomcat, Weblogic, Dynamo, Orion, Resin) is that files under
WEB-INF/lib will be picked up on the servlet CLASSPATH.
Using iAS 6 SP3 however, the deploytool seems to unjar all the JAR files under WEB-INF/lib, which is
fine except that some of my classes aren't being picked up. My custom tag classes are being found,
but org.xml.sax.XMLReader is not found, even though the class file exists.
Any idea what is happening here?
Thanks
Mat.

Hi Barry,
Where was your course held out of interest ? Ours was in Holland.
Wildcards definitely work as we tried this on the course.
Alternatively, you could make sure the directory you are processing only has files in for this process and nothing else then you could process everything regardless of the name just use .
Good luck with your processing.
If this helps, please award the points as so few people do
You can do this by clicking on the yellow star next to my answer.
Cheers
Colin

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Hi MSoldier.
There are two ways to do this:
1) You use the java.lang.Runtime classes to start the java application in your JAR file, just like you would have done it from the command line. The Runtime class has three different exec() methods that can be used to run any program just like you would from the command line. Remember, using this method you will have to write everything just like if you run your Java application from the command line, incl. classpath etc. This way your Java application will be run as a separate process. When the application finishes the process is shutdown and the resources (RAM etc.) taken by it freed, just like when you shutdown any other application.
2) You can open the JAR file yourself from inside the JSP page, look inside the META-INF file to find the main class, and then calls the main class main method. There is an example of how to do this in the Java Tutorial available from Sun under the JAR files track. Check these links :
The Java Tutorial at Sun
http://java.sun.com/docs/books/tutorial/
The JAR File Tutorial at Sun
http://java.sun.com/docs/books/tutorial/jar/index.html
Opening JAR Files via the Java JAR File API
http://java.sun.com/docs/books/tutorial/jar/api/index.html
Note however, if you have just created some classes that you want to use from inside your JSP pages, and not a separate application that needs to be run separately, you should just include the JAR file with your custom classes inside the WEB-INF/lib directory. These classes are then automatically available to your JSP pages, just like the rest of the Java API.
I hope this answers your questions,
Kind Regards,
Jakob Jenkov
Software Architect
Jenkov Development
www.jenkov.com

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Yes, use ZipOutputStream.
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[url=
http://forum.java.sun.com/thread.jsp?forum=421&thread=425724&tstart=0&trange=100
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at com.sun.javafx.tk.quantum.QuantumToolkit.startup(QuantumToolkit.java:
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>
Manifest-Version: 1.0
JavaFX-Version: 2.0
implementation-vendor: Oracle
implementation-title: BrickBreaker
implementation-version: 1.0
JavaFX-Application-Class: brickbreaker.Main
Created-By: JavaFX Packager
Main-Class: com/javafx/main/Main
>
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any body knows how to call a .jar file from a java bean?

Crosspost!
http://forum.java.sun.com/thread.jspa?messageID=4349619

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