NPE when using extend rules with or node and exists --------------------------------------------------- Key: DROOLS-809 URL: https://issues.jboss.org/browse/DROOLS-809 Project: Drools Issue Type: Bug Reporter: Jonathan MERCIER Assignee: Mario Fusco Dear In some case extended rule failed to find variable. {panel:title=NPE|borderStyle=dashed|borderColor=#ccc|titleBGColor=#F7D6C1|bgColor=#FFFFCE} Exception in thread "main" Exception executing consequence for rule "extended" in fr.cea.test: java.lang.NullPointerException at org.drools.core.runtime.rule.impl.DefaultConsequenceExceptionHandler.handleException(DefaultConsequenceExceptionHandler.java:39) at org.drools.core.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1125) at org.drools.core.phreak.RuleExecutor.fire(RuleExecutor.java:160) at org.drools.core.phreak.RuleExecutor.evaluateNetworkAndFire(RuleExecutor.java:108) at org.drools.core.common.DefaultAgenda.fireNextItem(DefaultAgenda.java:1016) at org.drools.core.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:1302) at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1289) at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1262) at fr.cea.test.App.main(App.java:57) Caused by: java.lang.NullPointerException at fr.cea.test.Rule_extended1921345119DefaultConsequenceInvokerGenerated.evaluate(Unknown Source) at fr.cea.test.Rule_extended1921345119DefaultConsequenceInvoker.evaluate(Unknown Source) at org.drools.core.common.DefaultAgenda.fireActivation(DefaultAgenda.java:1114) ... 7 more {panel} This occur when using "or", "exists" and "extends" A minimal test case is available on [github|https://github.com/bioinfornatics/DROOLS_NPE_rule_extended] In this [test case |https://github.com/bioinfornatics/DROOLS_NPE_rule_extended/blob/master/src/main/resources/fr.cea.test/rules.drl]: if we comment line number 35 , any error are raised if we uncomment line number 10 , any error are raised if we remove all "exists" words, any error are raised If the same rule is write using named consequence the test pass.