Yep, I know what you mean about building that jar.  I usually use the maven jar plugin in a maven build to do that: <plugin>     <groupId>org.apache.maven.plugins</groupId>     <artifactId>maven-jar-plugin</artifactId>     <configuration>         <archive>             <manifest>                 <mainClass>foo.bar.Bas</mainClass>                 <addClasspath>true</addClasspath>             </manifest>         </archive>     </configuration> </plugin> The "addClasspath" bit is keen.  That along with the maven dependency plugin gathers all the jars you need for the app.  (Sample pom.xml attached.) --- On Wed, 6/23/10, Wolfgang Laun <wolfgang.laun(a)gmail.com&gt; wrote: From: Wolfgang Laun <wolfgang.laun(a)gmail.com&gt; Subject: Re: [rules-users] execution using "java -jar x.jar ..." fails To: "Rules Users List" <rules-users(a)lists.jboss.org&gt;, "Edson Tirelli" <ed.tirelli(a)gmail.com&gt; Date: Wednesday, June 23, 2010, 2:29 PM OK. thanks. Here is a sample MANIFEST, to be included in the application jar, with the jars I've found essential for running a plain Expert application (without XML rules or commands): Manifest-Version: 1.0 Class-Path: /extra/drools-5.1.0.M2/drools-api-5.1.0.M2.jar /extra/drools-5.1.0.M2/drools-compiler-5.1.0.M2.jar /extra/drools-5.1.0.M2/drools-core-5.1.0.M2.jar /extra/drools-5.1.0.M2/lib/mvel2-2.0.16.jar /extra/drools-5.1.0.M2/lib/antlr-runtime-3.1.3.jar /usr/local/eclipse/plugins/org.eclipse.jdt.core_3.4.4.v_894_R34x.jar Main-Class: rss.aws.init.Main Eclipse's support for creating a jar isn't really helpful - I'd say it's confusing. I simply called    jar -fm myappl.jar MANIFEST ... # dirs where class and rules files are Thanks for the help. (My son simply said, "Why didn't you ask me?" - That's how it goes...) -W 2010/6/23 Greg Barton <greg_barton(a)yahoo.com&gt; See http://java.sun.com/j2se/1.4.2/docs/tooldocs/windows/java.html Key line' referring to the -jar option: "When you use this option, the JAR file is the source of all user classes, and other user class path settings are ignored." You can specify the path to external jars in the manifest of the standalone jar.   GreG On Jun 23, 2010, at 9:44 AM, Wolfgang Laun <wolfgang.laun(a)gmail.com&gt; wrote: The application works fine in Eclipse. In Eclipse, I created a jar file x.jar from the .class and a few .drl files, and copied x.jar to /tmp/x/ Now, in /tmp/x    CP="droos/*:drools/lib/*"    java -cp "$CP" -jar dpvt.jar par... This fails on the first attempt to access any class from a drools jar file. In /tmp/x, I unpack x.jar and call    CP="droos/*:drools/lib/*:."    java -cp "$CP" rss.aws.init.Main par... AND THIS WORKS! So, what is different when starting a Java program with java -jar as opposed to java x.y.Main? The stack dump is not very informative: java.lang.NoClassDefFoundError: org/drools/KnowledgeBaseFactory     at rss.aws.engine.impl.DroolsEngine.setup(DroolsEngine.java:30)     at rss.aws.init.Core.init(Core.java:51)     at rss.aws.init.Core.getInstance(Core.java:16)     at rss.aws.init.Main.<init>(Main.java:35)     at rss.aws.init.Main.main(Main.java:191) Caused by: java.lang.ClassNotFoundException: org.drools.KnowledgeBaseFactory     at java.net.URLClassLoader$1.run(URLClassLoader.java:217)     at java.security.AccessController.doPrivileged(Native Method)     at java.net.URLClassLoader.findClass(URLClassLoader.java:205)     at java.lang.ClassLoader.loadClass(ClassLoader.java:319)     at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)     at java.lang.ClassLoader.loadClass(ClassLoader.java:264)     at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:332)     ... 5 more  Any ideas? -W _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users -----Inline Attachment Follows----- _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users