The exception "java.lang.VerifyError:" occurs when there are conflicting versions of the same classes/jars are on the class path.
For instance when trying to create an Event using Event.createEvent with XPATH 2.0, the below error occurs.
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java.lang.VerifyError: Cannot inherit from final class
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:763)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
at java.net.URLClassLoader$1.run(URLClassLoader.java:368)
at java.net.URLClassLoader$1.run(URLClassLoader.java:362)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:361)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:338)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at com.tibco.genxdm.bridge.xinode.atomic.XiAtomBridge.<init>(XiAtomBridge.java:139)
at com.tibco.genxdm.bridge.xinode.typed.XiTypedContext.<init>(XiTypedContext.java:49)
at com.tibco.genxdm.bridge.xinode.XiProcessingContext.getTypedContext(XiProcessingContext.java:156)
at com.tibco.be.functions.xpath.BESchemaComponentCacheManager.getTypedContext(BESchemaComponentCacheManager.java:273)
at com.tibco.be.functions.xpath.XSLT2Helper.doTransform(XSLT2Helper.java:55)
at com.tibco.be.functions.event.EventHelper.createEvent3(EventHelper.java:275)
at com.tibco.be.functions.event.EventHelper.createEvent(EventHelper.java:240)
at com.tibco.be.functions.event.EventHelper.createEvent2(EventHelper.java:207)
at be.gen.RuleFunctions.Preprocessors.Internal.nullonSRUSessionEndPreprocessor$9y002fEvents$9y002fAbstract$9y002fNotifyEndOfSession$.onSRUSessionEndPreprocessor(nullonSRUSessionEndPreprocessor$9y002fEvents$9y002fAbstract$9y002fNotifyEndOfSession$.java:40)
at be.gen.RuleFunctions.Preprocessors.Internal.onSRUSessionEndPreprocessor.invoke(onSRUSessionEndPreprocessor.java:11)
at com.tibco.cep.runtime.session.impl.RuleSessionImpl$4.doTxnWork(RuleSessionImpl.java:1152)
at com.tibco.cep.kernel.core.rete.BeTransaction.run(BeTransaction.java:141)
at com.tibco.cep.kernel.core.rete.BeTransaction.execute(BeTransaction.java:101)
at com.tibco.cep.runtime.session.impl.RuleSessionImpl.preprocessPassthru(RuleSessionImpl.java:1176)
at com.tibco.cep.runtime.service.cluster.ClusterTaskController$1.doTxnWork(ClusterTaskController.java:78)
at com.tibco.cep.kernel.core.rete.BeTransaction.run(BeTransaction.java:156)
at com.tibco.cep.kernel.core.rete.BeTransaction.execute(BeTransaction.java:101)
at com.tibco.cep.runtime.service.cluster.ClusterTaskController.executeTask(ClusterTaskController.java:103)
at com.tibco.cep.runtime.scheduler.impl.WorkerBasedControllerV2$WorkerTask.run(WorkerBasedControllerV2.java:521)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at com.tibco.cep.runtime.util.CustomBEManagedThread.run(CustomBEManagedThread.java:24)
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This was because of class path issue with the environment, where conflicting versions of the same classes/jars are on the class path. Therefore while loading the classes a parent class, marked as a final class, is loaded from the incorrect jar.