WAR meta-inf/manifest Class-Path jars use which classloader ?

If using an expanded EAR structure, my Web App requires some utility classes. I
can either put these in my :-
meta-inf/manifest.mf
Class-Path : utility.jar
OR
web-inf/lib
can contain the utility.jar
Is there any difference in terms of which classloader is used to load these classes,
the EAR/EJB classloader or the Web App child classloader ?
What is recommended ?

If have found out the answer myself by testing it :-
A jar in the meta-inf/manifest.mf e.g. Class-Path : utility.jar
will be loaded by the EAR/EJB level classloader
whereas
web-inf/lib containing utility.jar
will be loaded by the Web App level child classloader.
Dimitri Rakitine <[email protected]> wrote:
I have this question too - it appears that 6.1sp2 attempts to use Class-Path
in jars in WEB-INF/lib - what this Class-Path: is supposed to do ???
Pete <[email protected]> wrote:
If using an expanded EAR structure, my Web App requires some utilityclasses. I
can either put these in my :-
meta-inf/manifest.mf
Class-Path : utility.jar
OR
web-inf/lib
can contain the utility.jar
Is there any difference in terms of which classloader is used to loadthese classes,
the EAR/EJB classloader or the Web App child classloader ?
What is recommended ?--
Dimitri

Similar Messages

How to use ClassPath defined in META-INF/MANIFEST.MF in an EAR

Hi,
We have an EAR Shared Library (Name = AA) deployed in Weblogic. EAR contents are like ->
APP-INF/lib/directoryA/<<50 JAR Files>>
META-INF/MANIFEST.MF --->> Has Class Path to above JAR files, Spec Version, Impl Version etc
META-INF/application.xml
META-INF/weblogic.application.xml
This EAR is deployed as Shared Library, and our EJB (name = BB) refers to this EAR. Now the problem we are facing is that the JARs are not reachable by EJB BB. If we restructure the Shared Library project so that all the JARS are under APP-INf/lib/ directory, we are able to access the JARS from EJB BB. (This means that we are referring the shared library correctly, using "library-ref" tag correctly.
Is there a way we can specify EJB BB to look for CLASS PATH as present in the MANIFEST.MF file of the Shared Library ??
Thanks,

WebLogic specifies a separate classloader for the APP-INF/lib directory that is why it gets loaded
When you have some.jar file placed in an arbitrary directory, for example, somewhere. You can either
use application.xml, for example,
<application ...>
 <module>
 <ejb>EJB.jar</ejb>
 </module>
 <module>
 <web>
 <web-uri>Web.war</web-uri>
 <context-root>MiddlewareMagic</context-root>
 </web>
 </module>
 <library-directory>somewhere</library-directory>
</application> Or by using the manifest Class-Path entry option which requires adding a META-INF/MANIFEST.MF file with the following contents:
Manifest-Version: 1.0
Class-Path: somewhere/some.jarMore information on class loading and application packaging can be found here: http://middlewaremagic.com/weblogic/?p=6725

WEB-INF/lib (.war) Vs META-INF/MANIFEST.MF (.ear)

What are the Class loading differences between libraries that are in a web application web-inf/lib and that are in class-path entry of META-INF/manifest.mf of a ear.
I recently developed a web services application with a ejb endpoint.Then
packaged it in a ear file with the classpath entry .The problem occured when I placed the weblogic.jar(and other third party jars) in the ear file which my ejb.jar uses as utility jar's. Jboss starts behaving weird.Some of the classes of jboss are overwritten and class cast exception errors started coming up.
Overnight I changed the application to a servlet end point and placed all my jars in the WEB-INF/lib then everything started working smooth.
Can any body help me , understand what is happening. Why doesn't j2ee have something like META-INF/lib

What did you do to resolve this issue .. I'm having the exact same problem.
What a nightmare.
I found approximately 40 forums on this topic (and
there are probably more), but noone has the definitive
answer!
Here's the problem....
My servlet uses a utility class that resides in some
other jar. That jar is then placed into the
WEB-INF\lib directory of the WAR which in turn goes
into the EAR. This is supposed to be all that is
needed in order for the utility class to be found on
the classpath.
In fact, if you run the war in Tomcat as a standalone
WAR it does in fact find it.... its when in an EAR
deloployed to app server that the problem arises.
I have had no luck with using any combination of
putting the jar ANYWHERE in the EAR or WAR no matter
if I specify the Class-Path: in the manifest(s) or
not.
I thought maybe that I was missing some config in the
application.xml or web.xml but I couldn't find
anything to support that.
Maybe its dependent on the app server? I am using
Orion, but the same problem can be found on J2EE RI
release 1.3
Work arounds:
1. Simply put the utility jar in the lib directory of
the server you're using
2. Add an ejb module to the application.xml naming the
utility jar as the ejb jar. Of course this is NOT an
EJB jar and error messages/warnings will appear
accordingly, but on Orion at least, it will load the
classes needed... hooray!!
Anyone got a definitive answer?

Classloader isolation and jar manifest Class-Path headers

I have a system where I am loading a set of jars, each with its own URL classloader. So, Jar a is loaded by Loader A, jar b is loaded by Loader B, and so on.
Each jar has a Manifest Class-Path entry declaring its dependence on other jars. So in the example above, a puts c.jar in its Class-path, and, let's say, b also puts c.jar in its Class-path, unbeknownst to a.
Let's say there's a class Foo in c.jar. I want--need--it to be the case that (loader of a.jar == Foo.class.getClassLoader()) from the perspective of classes found in a.jar, and (loader of b.jar == Foo.class.getClassLoader()) from the perspective of classes found in b.jar.
That is, I want a and b to have their own isolated "copies" of c.jar.
Instead, what I'm finding is that Foo.class is loaded once, and his loader "leaks" over to the other jar's loader, if that makes any sense.
Is there any way to accomplish what I am talking about here?
Laird

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.
Now that application reads, let's say, a properties file containing a list of URLs that point to jars.
Now the application creates a new URLClassLoader for each such URL. So if the mythical properties file has ten lines, then I create ten classloaders, each of which points to one and only one URL.
My problem is, even classes loaded by these isolated, separate classloaders are "leaking" across to other loaders. Remember, the parent classloader of all of these classloaders can't see the jars. Its classpath was empty, remember?
The issue is that the findLoadedClass() method of java.lang.ClassLoader scans the whole VM to see if a given Class was loaded before, and if it was, then by default that Class is simply returned. But I don't want that behavior.
Now, I also don't want the behavior of having to load the silly things off disk each and every time. So how do I retain this true multiple classloader isolation?
Thanks,
Laird

Verify a jar's manifest class-path

I want to verify a jar file's manifest class-path. By that I mean I want to verify that every import of every class in the jar file is reachable on the classpath specified in the jar file's manifest. I tried using a ClassLoader to load every class in the jar file and that does indeed catch a few errors (imported classes that are not on the classpath), but it does not catch them all -- I have situations where loading the class works fine, but when the code is executed, I get NoClassDefFoundError because an imported class is missing from the classpath. I have tried things like calling getDeclaredMethod() on the loaded class to sortof force all the imports to be resolved, but that apparently does not work.
So, can someone tell me how to sortof "force" a loaded class to reference/validate all its imports?
Thanks,
Lee

Well yes, I know that executing the code would do it. But I'm not in a position to execute the code -- I'm doing this during a build and want to verify that I've built all the jars properly and have all the right classpaths. It's actually quite easy to use ANT to compile and create jar files that produce NoClassDefFoundError at runtime, due to leaving needed classes from the jar, or from bogus classpaths in the jar's manifest.
So, I was hoping there was some other way to do this. Perhaps I need to do something ugly like examining the bytecodes of each method...
Thanks,
Lee

WAR Can't find class in JAR file in EAR/lib

Hi,
I have 1 EAR file with 1 WAR and 1 EJB-JAR file. Our main business-code is in a JAR-file which is placed in the EAR/lib/ folder along with the rest of the shared JAR-files.
When i deploy the EAR the EJB gets deployed fine but when the WAR gets deployed, we get a ClassNotFoundException. We configured a class as a ServletContextListener (Which is part of the jar) in the web.xml so at startup it should perform some initiation. But since it can;t be found....
I've tried changing the Mainfest.mf to include a CLASSPATH attribute with ./lib/x.jar but it stil the same problem. The only thing that solves it is to put it in the WEB-INF/lib folder.
What am i doing wrong?
Thanks,
Maarten

Here it is
<?xml version="1.0"?>
<!DOCTYPE application PUBLIC '-//Sun Microsystems, Inc.//DTD J2EE Application 1.3//EN' 'http://java.sun.com/dtd/application_1_3.dtd'>
<application>
 <display-name>spg-online</display-name>
 <module>
 <web>
 <web-uri>appname.war</web-uri>
 <context-root>appname</context-root>
 </web>
 </module>
 
</application>
My app follows the basic structure of an EAR-file:
EAR
META-INF
application.xml
lib
appname.jar
a.jar
spring.jar
appname.war
appname-ejb.jar
The meta-inf of the war-file looks like this:
Manifest-Version: 1.0
Ant-Version: Apache Ant 1.6.5
Created-By: 1.4.2_08-b03 (Sun Microsystems Inc.)
Class-path: ./lib/appname.jar ./spring.jar
I let ANT generate the Class-path:
<jar jarfile="${dist.home}/${component.name}.war">
<fileset dir="${build.home.webroot}" />

<manifest>
<attribute name="Class-Path" value="${lib.project.manifest.classpath}"/>
</manifest>
</jar>

J2EE Packaging and manifest Class-Path:

Does anyone know if Weblogic 6.0 supports the redefined deployment extension mechanism
that makes use of the 'Class-Path:' entry in the manifest files?
In our project we have one single .ear file containing a couple of EJB's (.jar
files) and a Web Application (.war file).
We are using log4j as logging mechanism and we would like to keep everything in
the .ear file so that we can make hot-deploys. So we are trying not to make use
of the classpath in startWebLogic.sh. All of our EJB's and the Web Application
makes use of log4j.jar. My question is; can I do the following and make it work
in Weblogic 6.0?
1. In every EJB .jar file I add the follwing to the manifest file - "Class-Path:
log4j.jar"
2. I place the log4j.jar in the root directory of the .ear file.
By doing this I expect that the ear classloader loads the log4j.jar classes. Am
I right or do I do something wrong. At least it does not seem to work.
Using Weblogic 6.0 without service pack.
Thanks,
Steen

This does not work in WebLogic 6.0. It's supposed to be supported in 6.1
Daniel
-----Original Message-----
From: Steen Laursen [mailto:[email protected]]
Posted At: Wednesday, August 08, 2001 1:32 PM
Posted To: environment
Conversation: J2EE Packaging and manifest Class-Path:
Subject: J2EE Packaging and manifest Class-Path:
Does anyone know if Weblogic 6.0 supports the redefined
deployment extension mechanism
that makes use of the 'Class-Path:' entry in the manifest files?
In our project we have one single .ear file containing a
couple of EJB's (.jar
files) and a Web Application (.war file).
We are using log4j as logging mechanism and we would like to
keep everything in
the .ear file so that we can make hot-deploys. So we are
trying not to make use
of the classpath in startWebLogic.sh. All of our EJB's and
the Web Application
makes use of log4j.jar. My question is; can I do the
following and make it work
in Weblogic 6.0?
1. In every EJB .jar file I add the follwing to the manifest
file - "Class-Path:
log4j.jar"
2. I place the log4j.jar in the root directory of the .ear file.
By doing this I expect that the ear classloader loads the
log4j.jar classes. Am
I right or do I do something wrong. At least it does not seem
to work.
Using Weblogic 6.0 without service pack.
Thanks,
Steen

Unable to read TLD "META-INF/jsf_core.tld" from JAR file "file:

Hallo everybody :-) i've installed Workflow-Server + ARES + FormManager. When i call localhost:8080/adminui i can log in and the browser loads the next site --> it fails and says: org.apache.jasper.JasperException: Unable to read TLD "META-INF/jsf_core.tld" from JAR file "file:/C:/Adobe/LiveCycle/jboss/server/all/tmp/deploy/tmp56414LiveCycle.ear-contents/admi nui.war/WEB-INF/lib/jsf-impl.jar": org.apache.jasper.JasperException: Failed to load or instantiate TagExtraInfo class: com.sun.faces.taglib.FacesTagExtraInfo org.apache.jasper.compiler.DefaultErrorHandler.jspError(DefaultErrorHandler.java:5 0) org.apache.jasper.compiler.ErrorDispatcher.dispatch(ErrorDispatcher.java:409) org.apache.jasper.compiler.ErrorDispatcher.jspError(ErrorDispatcher.java:183) org.apache.jasper.compiler.TagLibraryInfoImpl.<init>(TagLibraryInfoImpl.java:181) org.apache.jasper.compiler.Parser.parseTaglibDirective(Parser.java:418) org.apache.jasper.compiler.Parser.parseDirective(Parser.java:483) org.apache.jasper.compiler.Parser.parseElements(Parser.java:1539) org.apache.jasper.compiler.Parser.parse(Parser.java:126) org.apache.jasper.compiler.ParserController.doParse(ParserController.java:220) org.apache.jasper.compiler.ParserController.parse(ParserController.java:101) org.apache.jasper.compiler.Compiler.generateJava(Compiler.java:203) org.apache.jasper.compiler.Compiler.compile(Compiler.java:470) org.apache.jasper.compiler.Compiler.compile(Compiler.java:451) org.apache.jasper.compiler.Compiler.compile(Compiler.java:439) org.apache.jasper.JspCompilationContext.compile(JspCompilationContext.java:511) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:295) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:292) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:236) javax.servlet.http.HttpServlet.service(HttpServlet.java:810) com.sun.faces.context.ExternalContextImpl.dispatch(ExternalContextImpl.java:322) com.sun.faces.application.ViewHandlerImpl.renderView(ViewHandlerImpl.java:130) com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:87) com.sun.faces.lifecycle.LifecycleImpl.phase(LifecycleImpl.java:200) com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:117) javax.faces.webapp.FacesServlet.service(FacesServlet.java:198) com.adobe.framework.SecurityFilter.doFilter(SecurityFilter.java:177) com.adobe.idp.um.auth.filter.PortalSSOFilter.doFilter(PortalSSOFilter.java:106) com.adobe.framework.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter .java:161) Any idea what' wrong? Thanks, Valerio

Hi Howard,
thank you for your post.
I actually new about the problems with the jvm version. Still i wanted to ask, cause there are different reports on this `java problems` and even though the 1.4.2_08 seems to be the best version (by the way this version is not to be downloaded any longer *sig*), there are people getting all installed with other versions. I couldn't find any regularity in the misbehavior of the servers while installing.
I finally achieved and got everything working ... but very slow. Loading the adminui or BAM features takes very long time (over one minute). Have you already had this delay. Any hint?
Thanks again,
Valerio

Manifest class-path does not works

Hi,
We use Jrockit 1.4.2 (latest) on Solaris.
We found that manifest class-path does not seems to work, we got classdef not found messages.
If we change the JVM to sun 1.4.2 that everything works perfectly.
Manifest:
Manifest-Version: 1.0
Ant-Version: Apache Ant 1.5.2
Created-By: 1.4.1_02-b06 (Sun Microsystems Inc.)
Implementation-Title: com.clarify.igb.common.ejbserver
Implementation-Version: 12.5.000
Implementation-Vendor: Amdocs Inc.
Specification-Title: ClarifyCRM Business Object Infrastructure
Specification-Version: 12.5.000
Specification-Vendor: Amdocs Inc.
Class-Path: ClfyShared.jar ClfyCbo.jar ClfyClient.jar ClfyWebInf.jar C
lfyiSupport.jar ClfyUtil.jar jdom.jar ClfyCommon.jar ClfySales.jar Cl
fymOrder.jar ClfyiAdmin.jar ClfyBilling.jar ClfyBillingManager.jar Cl
fyEmailProcessor.jar
What can be the problem?
Regards.,
LJ

Hi Jaejun,
a.jar should also have a MANIFEST.MF Class-Path refering to b.jar.
HTH
Regards,
Slava Imeshev
"Jaejun Lee" <[email protected]> wrote in message
news:3e541ede$[email protected]..
>
I meant <CRLF> not <CR> only.
Thank you.
"Jaejun Lee" <[email protected]> wrote:
Ravinder Pal <[email protected]> wrote:
I have read all message posted in this regard but my problem still
remain.
Please read the context to give me some pointers.
myapp.ear contains
- myejb.jar contains
- manifest with Class-Path a.jar b.jar
- a.jar (Internal)
- b.jar (Some external Vendor)
Problem: Call from a.jar classes which reference b.jar classes doesraise
a ClassNotFoundException.
Thanks.
I have a similar problem with WebLogic 7.0 sp1.
I have to verify this.
Dose WebLogic support MANIFEST.MF Class-Path in development-mode.
Indeed, I just put a.jar and b.jar in application directory.
I put Class-Path: b.jar<carrage-return> in MANIFEST.MF of a.jar.
But, a.jar cannot find classes in b.jar.
Do I have to make EAR?

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:
<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]

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:
<web web-app-class-loader include-war-manifest-class-path="true"/>
^^^
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

Error while reading 'META-INF/weblogic-cmp-rdbms-jar.xml

Hi,
I am getting an error running appc. I am upgrading from wl 7 to wl 8.1. ejbc works
fine on wl 7. Anyone seen this before?
[J2EE:160121]Errors encountered while compiling module 'e:\dev\xstatic\tmp\xstatic_Intermediate.jar':
[EJB:011017]Error while reading 'META-INF/weblogic-cmp-rdbms-jar.xml'. The error
was:
java.lang.NullPointerException
at weblogic.ejb20.cmp.rdbms.finders.ExprWHERE.init_method()V(ExprWHERE.java:47)
at weblogic.ejb20.cmp.rdbms.finders.BaseExpr.init(Lweblogic.ejb20.cmp.rdbms.finders.QueryContext;Lweblogic.ejb20.cmp.rdbms.finders.QueryNode;)V(BaseExpr.java:230)
at weblogic.ejb20.cmp.rdbms.finders.ExprROOT.init_method()V(ExprROOT.java:89)
at weblogic.ejb20.cmp.rdbms.finders.BaseExpr.init(Lweblogic.ejb20.cmp.rdbms.finders.QueryContext;Lweblogic.ejb20.cmp.rdbms.finders.QueryNode;)V(BaseExpr.java:230)
at weblogic.ejb20.cmp.rdbms.finders.QueryContext.generateQuery()V(QueryContext.java:91)
at weblogic.ejb20.cmp.rdbms.finders.Finder.computeSQLQuery(Lweblogic.ejb20.cmp.rdbms.RDBMSBean;)V(Finder.java:1002)
at weblogic.ejb20.cmp.rdbms.RDBMSBean.generateFinderSQLStatements(Ljava.util.Iterator;)V(RDBMSBean.java:2692)
at weblogic.ejb20.cmp.rdbms.Deployer.readTypeSpecificData(Ljava.io.InputStream;Ljava.lang.String;)V(Deployer.java:479)
at weblogic.ejb20.persistence.PersistenceType.setTypeSpecificFile(Lweblogic.ejb20.interfaces.EntityBeanInfo;Lweblogic.ejb20.persistence.spi.CMPDeployer;)V(PersistenceType.java:483)
at weblogic.ejb20.persistence.PersistenceType.setupDeployer(Lweblogic.ejb20.interfaces.EntityBeanInfo;Ljava.io.File;Lweblogic.utils.Getopt2;Lweblogic.utils.jars.VirtualJarFile;)Lweblogic.ejb20.persistence.spi.CMPDeployer;(PersistenceType.java:414)
at weblogic.ejb20.deployer.CMPInfoImpl.setup(Ljava.io.File;Lweblogic.utils.Getopt2;Lweblogic.utils.jars.VirtualJarFile;)V(CMPInfoImpl.java:113)
at weblogic.ejb20.ejbc.EJB20CMPCompiler.generatePersistenceSources(Lweblogic.ejb20.interfaces.EntityBeanInfo;Lweblogic.utils.jars.VirtualJarFile;)Ljava.util.List;(EJB20CMPCompiler.java:64)
at weblogic.ejb20.ejbc.EJBCompiler.doCompile(Ljava.util.Collection;Lweblogic.utils.jars.VirtualJarFile;)V(EJBCompiler.java:245)
at weblogic.ejb20.ejbc.EJBCompiler.compileEJB(Lweblogic.utils.classloaders.GenericClassLoader;Lweblogic.management.configuration.EJBComponentMBean;Lweblogic.management.descriptors.toplevel.EJBDescriptorMBean;Lweblogic.utils.jars.VirtualJarFile;Lweblogic.j2ee.valid
ation.ModuleValidationInfo;Lweblogic.ejb20.ejbc.VersionHelper;Ljava.util.Collection;)V(EJBCompiler.java:468)
at weblogic.ejb20.ejbc.EJBCompiler.compileEJB(Lweblogic.utils.classloaders.GenericClassLoader;Lweblogic.utils.jars.VirtualJarFile;Lweblogic.j2ee.validation.ModuleValidationInfo;)V(EJBCompiler.java:387)
at weblogic.appc.compileEJB(Lweblogic.utils.classloaders.GenericClassLoader;Lweblogic.utils.jars.VirtualJarFile;Ljava.io.File;Lweblogic.j2ee.validation.ModuleValidationInfo;)V(appc.java:735)
at weblogic.appc.compileEJB()V(appc.java:709)
at weblogic.appc.compileInput()V(appc.java:446)
at weblogic.appc.runBody()V(appc.java:167)
at weblogic.utils.compiler.Tool.run([Ljava.lang.String;)V(Tool.java:146)
at weblogic.utils.compiler.Tool.run()V(Tool.java:103)
at weblogic.appc.main([Ljava.lang.String;)V(appc.java:961)

It is a bug for the EJB container to respond with an NPE.
(It's been fixed in v9 Beta, and it might be fixed in an 8.1 service pack but I can't recall off the top of my head). At any rate, I'm pretty sure that an EJB QL query with an empty WHERE clause will cause this. I would look for a query that ends in ' WHERE'.
-thorick

Manifest Class-Path: attribute setting

          Hi there,
          Though the classpath entry is made it is not reacting as expected...Need help
          in understanding the classpath attribute behaviour on web Logic Server 7.0...
          how do I make a jar file inside a war file(war/WEB-INF/lib)refer another jar file
          outside this war.


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

Jar's manifest Class-Path option

Hey, hopefully this is my last question for a while.
I downloaded a custom look and feel that's packaged in a jar file.
Here's the directory structure.
Main-Program\*.class
Main-Program\MyProgram.jar (the created jar)
Main-Program\Data\kunststoff.jar (downloaded look&feel jar)
I can compile the class files like this:
javac -classpath .;Data\kunststoff.jar MainClass.java
and run it like this:
java.exe -classpath .;Data\kunststoff.jar MainClass
This works fine. But I want my program to be an executable jar.
So I create the exec. jar like usual
jar cf0 MyProgram.jar *.class
jar umf mainclass.txt MyProgram.jar
When I package the jar using the manifest file I include the Class-Path var:
Manifest-Version: 1.0
Main-Class: Database
Class-Path: .;Data\kunststoff
Now when I try to execute the jar it gives me the error:
"Could not find the main class. Program will exit!"
Any ideas? thanks.

Manifest-Version: 1.0
Main-Class: Database
Class-Path: .;Data\kunststoff>
Better change that to "Class-Path: Data/kunststoff.jar"
(http://java.sun.com/docs/books/tutorial/jar/basics/manifest.html)
And remember to have a line break after it..
Now when I try to execute the jar it gives me the
error:
"Could not find the main class. Program will exit!">
But the main class should still be found even if the class-path entry was not totally correct, does Database.class show in jar tf MyProgram.jar?

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?

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:
Class-Path: /Oracle/Ora81/jdbc/lib/classes12.zip /Oracle/Ora81/jdbc/lib/classese111.zip
When I move the jar file to unix, the classpath will be changed, is there a way to make the jar file read the class-path from system CLASSPATH?
Thank you.
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.
thanks in advance
Eran

WAR meta-inf/manifest Class-Path jars use which classloader ?

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