Note: I originally tried posting this as a reply to this <http://drools.46999.n3.nabble.com/Upgrade-to-protobuf-2-5-and-how-to-work... , before I realized it was the wrong mailing list. _____ It looks like moving from protobuf-java v.2.4.1 to v.2.5.0 has non-passive changes that are causing more troubles preventing an upgrade to Drools v.6.x. Explained here <https://code.google.com/p/protobuf/issues/detail?id=493> Our Drools rules are ran in an environment that must share a classpath with Hadoop libs. These libs are still using protobuf-java v.2.4.1 and cannot easily be upgraded. The problem comes down to a runtime error: ``` 2014-03-11 06:39:25,229 FATAL org.apache.hadoop.mapred.Child: Error running child : java.lang.VerifyError: class org.drools.compiler.kie.builder.impl.KieModuleCache$KModuleCache overrides final method getUnknownFields.()Lcom/google/protobuf/UnknownFieldSet; at java.lang.ClassLoader.defineClass1(Native Method) at java.lang.ClassLoader.defineClassCond(ClassLoader.java:631) at java.lang.ClassLoader.defineClass(ClassLoader.java:615) at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141) at java.net.URLClassLoader.defineClass(URLClassLoader.java:283) at java.net.URLClassLoader.access$000(URLClassLoader.java:58) at java.net.URLClassLoader$1.run(URLClassLoader.java:197) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:190) at java.lang.ClassLoader.loadClass(ClassLoader.java:306) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301) at java.lang.ClassLoader.loadClass(ClassLoader.java:247) at org.drools.compiler.kie.builder.impl.KieBuilderImpl.createCacheBuilder(KieBuilderImpl.java:269) at org.drools.compiler.kie.builder.impl.KieBuilderImpl.generateKieModuleMetaInfo(KieBuilderImpl.java:224) at org.drools.compiler.kie.builder.impl.KieBuilderImpl.buildAll(KieBuilderImpl.java:194) <... application level omitted ...> ``` This error makes sense given the changes in protobuf-java v.2.5. I do not believe that our use-case of the Drools rules engine involves the use of any of the features of the `KieModuleCache` and marshalling/unmarshalling libs associated with it. However, I do not see any sort of configuration that would avoid this error. I tried to simply use the "legacy" Drools knowledge-api when upgrading to Drools v.6.x, but this has failed us since there are several unimplemented methods in the `org.drools.impl.adapters.KnowledgeRuntimeAdapter`, such as `org.drools.impl.adapters.KnowledgeRuntimeAdapter#getQueryResults`. Side note: I expected the knowledge-api to be fully-functional and implemented in Drools v6.x for backwards compatibility and for tooling integration <http://docs.jboss.org/drools/release/6.0.1.Final/drools-docs/html_single/... . However, this does not seem to be the case at this point. We are eager to move to Drools v6.x to avoid some performance issues we are facing due to performance issues with eagerly evaluating `AccumulateNode` results that are accumulating large collections <http://drools.46999.n3.nabble.com/Object-size-impact-on-session-insertion... . Do you have any suggestions? -- View this message in context: http://drools.46999.n3.nabble.com/Upgrade-to-protobuf-2-5-Prevents-Upgrad... Sent from the Drools: User forum mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users

Upgrading Hadoop is not possible for sometime still. It requires a fairly large coordinated effort. I don't suppose there is any chance that there will be a workaround for this in Drools 6? Perhaps a configuration options or something?

-- View this message in context: http://drools.46999.n3.nabble.com/Upgrade-to-protobuf-2-5-Prevents-Upgrad... Sent from the Drools: User forum mailing list archive at Nabble.com. _______________________________________________ rules-users mailing list rules-users(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/rules-users