Dynamically load different versions of client jar

Hello,
My application needs to simultaneously support different versions of an RMI app. How to dynamically load the proper version of the client jar to connect with the same version of the server. Say Server versions are sv1.0, sv 1.1, sv 2.0 and clients are cl1.0, cl1.1, cl2.0. How to dyncamically load cl1.0 in my application so as to connect with sv1.0, similarly cl1.1 with sv1.1
Will having a different classloader for each of the client jars, solve the problem?
Can someone direct me/suggest on how to handle this.
I appreciate your help and thanks for your time.

Try this link if you want to see how browser based help will look on MACs and Apple hardware.
http://www.grainge.org/demos/bbair/
Your developers would need to create a sniffer to ascertain the OS of the user's device and then route to the required help. That is not built into RoboHelp and RoboHelp Server will not assist with this one.
See www.grainge.org for RoboHelp and Authoring tips
@petergrainge

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Try this link if you want to see how browser based help will look on MACs and Apple hardware.
http://www.grainge.org/demos/bbair/
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Hi all
At the moment I am fighting with some class loading issues in a J2EE Appcontainer... Acutally the app server uses a different version of a jar file than my application.. Now the classloader always uses
the already loaded classes of the AppServers jar Version instead of those that I want..
I have my application together with the dependent jar packaged together into one jar file... In the manifest I lsit the dependency...
Now my question is if its possible to explicitly state the version of the package that my jar is dependent of...
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regards
tom

Vijay
Acutally I just read through the thread. Actually what I am working on is an J2EE App Containing a couple of EJB (2.0) components in different jars, some utility jars and 2 Wars. All this is packaged together into an ear.
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org.jdom.Document(1bb8ea).ClassLoader=org.jboss.system.server.NoAnnotationURLClassLoader@e3b895
..org.jboss.system.server.NoAnnotationURLClassLoader@e3b895
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ar-contents/tebs-migration-0.1-SNAPSHOT.jar-contents/jdom-b10.jar
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As I could not figure out how to solve this I came to the question regarding versioning... As both JDom.jars contain version information this would solve my probem... But as you already mentioned AFAIK there is only support to give some verision informationen about a jar in the manifest but nothing mentions that you can explicitely request a specific version.
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Can Oracle client dynamically link to Oracle shared libraries if the versions are different ?
Hi:
I apologize for this newbie question:
We are using PRO C to generate the client C code.
We can compile both dynamic and static versions of our Oracle client.
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is it possible to compile a dynamically linked Oracle client in say version 10.1.0.2 and actually run the application against say version 8.1.7.0 environment ?
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What you describe is not supported.

How to use two different versions of the same jar within one project

Hi everybody!
I have a big problem while integrating different web service clients within one bigger java project. Both implemetations need some jar files to work but demand different version. So, i would like to know if there is any way to tell which implementation should use which version! Anyhow i add those jars to the classpath makes working only one or the other webservice working but never both! Any ideas somebody?
Best regrads,
Stefan G�tz

Of course do have the jar files different names but the classes inside of them are the same ... means that the standard system classloader can distinguish them. When you add a jar to a classpath the name actually dosent matter.... any other ideas, please?
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http://java.sun.com/docs/books/tutorial/ext/basics/load.html

How to dynamically load jar files - limiting scope to that thread

Dynamically loading jar files has been discussed a lot. I have read a quite a few posts, articles, and demo code for doing just that. However, I have yet to find a solution to my problem. Most people modify their system class loader and are happy. I have done that and was happy for a time. Occasionally, you will see reference to an application server or tomcat or some other large project that have successfully been able to load and unload jar files, allow for dynamic deployment of code, etc. However, I have not been able to achieve similar success; And my problem is much less complicated.
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I am close, I am doing the following...
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Thanks to everyone - I got it working!
First, BenSchulz' s dumpClassLoader() method helped me to visualize the classLoader hierarchy. I am still not completely sure I understand why my initial class was always found by the systemClassLoader, but knowning that - was the step I needed to find the solution.
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The real problem turned out to be that my two isolating classes (the parent "MessageSender", and the child "QueueAdmin") were contained within the same jar file that was included in the classpath. This meant that no matter what I did the classes were loaded by the systemClassLoader. Isolating them in classes was just the first step. I had to remove them from my jar file and create another jar file just for those JMSClient specific classes. Then this jar file was only included int custom classLoader that I created when I wanted to instantiate a JMSClient session.
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psuedu code/concept ....
Primary Jar File   - Included in ClassPath
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MessageSender impliments Primary.JMSClientInterface{
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Dynamically load jar file

Hi,
I've got an applet (used in a website) which must internally load a jar (the jarname and mainclassname are stored in the database).
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Regards,
Thijs

It shouldn't be that difficult; all the stuff you need to build jars is in java.util.jar.*.
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Jars dependent on different versions of the another jar

I have two vendor supplied jars that are both dependent on different releases of another jar. So, in the usage instructions for the first jar, it says to make sure that x_1_2_1.jar is my classpath. Likewise, in the usage instructions for my other jar, it says to make sure that x_2_0_1.jar is in my classpath. The installers for each one of these jar puts their version of the dependent x jar in a subdirectory under their installation.
This causes all sorts of headaches because neither jar ever gets completely what it is looking for. Code in the jar that depends on x_1 fails if x_2 is in the classpath first, while code in the jar that depends on x_2 fails if x_1 is the classpath first.
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I was thinking that maybe the manifest Class-Path of each jar might be used to force where each jar looks for it's dependent jars, but the documentation I read about Manifests indicated that each jars Class-Path is simply concatenated into the overall Classpath that the ClassLoader uses.
If it matters, all this is in a Java 1.3.1 environment.
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Probably it is allowed. The following is cited from the Java Language Specification, 2nd edition (chapter 7.7, Unique Package Names, packages.doc.html):
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I'm programming an JDBC driver tester.
I have to load dynamically any driver from an archive (jar or zip) after the user uploaded it.
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I think there is in this case only one instance

Dynamically load different versions of client jar

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