Alternate drives in Jar file Class-Path attribute

Hello, all. I am working on a project that I would like to package into a single jar file for simple execution. At my place of work classes from EJB are stored on a different drive from where I am doing the development. I am having trouble accessing those classes from the Jars I am creating. When I try the following manifest:
Main-Class: MyPackage.MyClass
Class-Path: U:\someFolder
the application will not start, saying that MyPackage.MyClass cannot be found. This is despite MyPackage.MyClass being properly packaged into the Jar file, as verified by a jar t operation. When I leave off the drive letter in the Class-Path attribute:
Main-Class: MyPackage.MyClass
Class-Path: someFolder
the application starts and executes properly right up until a class from someFolder is needed, at which point exceptions begin to be thrown.
Any ideas will be much appreciated!
John Todd

I was eventually able to find the answer to my own question: Jars do not accept absolute paths at all, only relative paths. Thus, the alternate drive approach will not work. Fortunately I was able to find an alternate solution.
John Todd

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Who knows about Jar/Manifest: Class-Path-Attribute

My question is:
When packaging my classes and ressource files into a jar file, everything works fine as long as I put the manifest-file into the parent directory of the package folders (there's the main class too) and set its Class-Path-Attribut just as . (a dot).
I'm working with WinXP Prof.
As soon as I fill in a path with backslashes or slashes as separator, the produced jar-file doesn't work (class loader does'nt find main-class).
Is the problem the drive-letter (D:) in the path or do you know something else?
Greetings
Frank

Yes, and likely the . is what you need ...saying: I want the packages which begin in the same directory as the jar running this application. Even if your class is in a package hierarchy like tst.test.Support.class, if the directory tst is in the same directory as the application jar, you would use classpath . not tst/test/Support.class. If you put the tst package in a directory under the folder where the jar resides, say called testit ...you would then have a classpath in the mainifest like testit/. The class path always needs to get you to the root of any package you want to use ...but not into the package itself. Java recognizes when it is looking at a package nesting due to the package declaration syntax in the files, the classpath just points to the location of the root of that package and nothing more. Does this make sense?

Multiple Class-Path: attributes in Jar files

Hello,
I'm packaging a set of jar files for distribution with Class-Path: attributes in them. In the documentation I read and in one of the java trails it said that I could have a manifest file like:
Class-Path: log4j.jar log4j-core.jar
Class-Path: jsse.jar jcert.jar jnet.jar
But this doesn't work. It only works when I do this:
Class-Path: log4j.jar log4j-core.jar jsse.jar jcert.jar jnet.jar
Here is how I'm running the jar:
java -jar server.jar
Is the documentation wrong? Or this is a bug?
thanks
charlie

Certain attributes were only meant to be specified once. Like Main-Class and Class-Path for example. If these were listed two or more times, then the last occurance is the one that gets recognized (basically, each new instance overwrites the previous instance). Some attributes are listed as "per-entry" and are freely duplicated for each entry. For example signed jars could have a number of Name: and xxx-Digest: attributes.
This link is to the manifest spec:
http://java.sun.com/products/jdk/1.2/docs/guide/jar/manifest.html
To answer the original posters question, the doc's are in error. Actually, the error was not in the docs, it was in the tutorial, but none the less its still in error. He could have done this:
Class-Path: log4j.jar log4j-core.jar
jsse.jar jcert.jar jnet.jar
^-- two spaces before the start of jsse.jar
because the docs allow for line continuation (although it's not exactly clear if you read the docs). The docs are also apparently in error regarding the max line length of 72 bytes. I have tested this with over 100 char's on a win32 machine and it works fine for me. The limitation must therefore apply to some other operating system, or it could just be in error.
-Ron

Jar Class-Path attribute configuration problems

java version 1.5.0_14
OS: Windows Server 2003
Problem description: Executable jar file needs to access external jar file resources on the same server that executable jar file resides.
Scenario: Executable jar file resides in a directory called c:\Java. External jar file resides in a directory called c:\Java\itext1
I have attempted configuring the Class-Path attribute in the manifest with the following:
java/itext1/itext1.jar or entering itext1/itext1.jar
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c:\>java -jar /java/MyJar.jar
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BaseFont
I even unpacked the jar file, to see if I could access the class using the following command below (The class does not have a main method, so I did not expect it to execute, but I would have thought the class would have been located)
C:\>java java/itext1/com/lowagie/tools/BaseFont
Exception in thread "main" java.lang.NoClassDefFoundError: java/itext1/com/lowa
ie/tools/BaseFont
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The -jar flag tells the interpreter that the application is packaged in the JAR file format, and to my knowledge, has nothing to do with the classpath attribute within the manifest
At any rate, I found my problem. When packaging the jar via Eclipse, I had 2 .classpath resource files within the project, which was causing the jar fiile to be built incorrectly.

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Write
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How do I add the system classpath to Jar Manifest Class-Path

My application is implemented on win2000 and need to be moved to unix as a executable jar file, the oracle jdbc classes (classes12.zip and classes111.zip) were included in MANIFEST.MF as the following:
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Y.

I have the same problem for weeks now, and I can't seem to get it solved. If you found anything please inform me.
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As I understand the question - no.Hi; I think you misunderstand the question.
The classes are being loaded by the system loader.
Thus there is no way to seperate them.
If you want them seperate then you must use an
explicit class loader to load them.I am using explicit loaders to load them. Let me try again, because I don't think I was clear.
I have an application that has, let's say, nothing at all in its classpath. That is, it was invoked via "java ApplicationMainClass". No classpath.
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Can't jar files with paths 255 chars

Hi all,
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Help: manifest class path attribute - OC4J 9.0.3

I have tried everything I can think of. I have even downloaded the developers version of JRun to ensure my code does deploy under the J2EE spec.
Per compleating deployment under JRun, I have migrated back to OC4J and made the approperate modifications to orion-web.xml to include the following entry:
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Anyone got some sugestions?
Info: Ear deployment, static pages deploy under all wars...
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Andrew
[email protected]

I have tried everything I can think of. I have even downloaded the developers version of JRun to ensure my code does deploy under the J2EE spec.
Per compleating deployment under JRun, I have migrated back to OC4J and made the approperate modifications to orion-web.xml to include the following entry:
<web-app-class-laoder include-manifest-class-path="true" />
Even with this entry I get the same class not found statements. I am out of ideas.
Anyone got some sugestions?
Info: Ear deployment, static pages deploy under all wars...
Thanks.
Andrew
[email protected]
Hi Andy -
Can you check the attribute and make sure it's the following:
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^^^
You have have just typed it in quickly, but I noticed there's a typo in the entry you have above and you are missing the WAR piece of the attribute name.
There's a how-to document on OTN which has an example of this.
http://otn.oracle.com/tech/java/oc4j/htdocs/how-to-servlet-warmanifest.html
cheers
-steve- Hi Steve
Where can I find the zip file I went through the link but doesn't have any link to zip file
Thanks
Ritesh

Manifest Class-Path: attribute setting

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You looked into the Jar section of the Sun tutorial did you?

Jar File Class Caching

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Restart application or reload jar-file(class-files)

hi,
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Hi,
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Alternate drives in Jar file Class-Path attribute

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