Exception in thread "AWT-EventQueue-0" Exception executing consequence for rule "Talk required room tags" in org.optaplanner.examples.conferencescheduling.solver: java.lang.NullPointerException
	at org.drools.core.runtime.rule.impl.DefaultConsequenceExceptionHandler.handleException(DefaultConsequenceExceptionHandler.java:39)
	at org.drools.core.common.DefaultAgenda.handleException(DefaultAgenda.java:1242)
	at org.drools.core.phreak.RuleExecutor.innerFireActivation(RuleExecutor.java:439)
	at org.drools.core.phreak.RuleExecutor.fireActivation(RuleExecutor.java:380)
	at org.drools.core.phreak.RuleExecutor.fire(RuleExecutor.java:136)
	at org.drools.core.phreak.RuleExecutor.evaluateNetworkAndFire(RuleExecutor.java:89)
	at org.drools.core.concurrent.AbstractRuleEvaluator.internalEvaluateAndFire(AbstractRuleEvaluator.java:34)
	at org.drools.core.concurrent.SequentialRuleEvaluator.evaluateAndFire(SequentialRuleEvaluator.java:43)
	at org.drools.core.common.DefaultAgenda.fireLoop(DefaultAgenda.java:1062)
	at org.drools.core.common.DefaultAgenda.internalFireAllRules(DefaultAgenda.java:1009)
	at org.drools.core.common.DefaultAgenda.fireAllRules(DefaultAgenda.java:1001)
	at org.drools.core.impl.StatefulKnowledgeSessionImpl.internalFireAllRules(StatefulKnowledgeSessionImpl.java:1330)
	at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1321)
	at org.drools.core.impl.StatefulKnowledgeSessionImpl.fireAllRules(StatefulKnowledgeSessionImpl.java:1305)
	at org.optaplanner.core.impl.score.director.drools.DroolsScoreDirector.calculateScore(DroolsScoreDirector.java:171)
	at org.optaplanner.examples.common.business.SolutionBusiness.getScore(SolutionBusiness.java:221)
	at org.optaplanner.examples.common.swingui.SolverAndPersistenceFrame.resetScreen(SolverAndPersistenceFrame.java:723)
	at org.optaplanner.examples.common.swingui.SolverAndPersistenceFrame.setSolutionLoaded(SolverAndPersistenceFrame.java:690)
	at org.optaplanner.examples.common.swingui.SolverAndPersistenceFrame$QuickOpenAction.actionPerformed(SolverAndPersistenceFrame.java:250)
	at org.optaplanner.examples.common.swingui.SolverAndPersistenceFrame.lambda$createQuickOpenPanel$0(SolverAndPersistenceFrame.java:205)
	at javax.swing.JList.fireSelectionValueChanged(JList.java:1802)
	at javax.swing.JList$ListSelectionHandler.valueChanged(JList.java:1816)
	at javax.swing.DefaultListSelectionModel.fireValueChanged(DefaultListSelectionModel.java:184)
	at javax.swing.DefaultListSelectionModel.fireValueChanged(DefaultListSelectionModel.java:154)
	at javax.swing.DefaultListSelectionModel.setValueIsAdjusting(DefaultListSelectionModel.java:685)
	at javax.swing.JList.setValueIsAdjusting(JList.java:2146)
	at javax.swing.plaf.basic.BasicListUI$Handler.mouseReleased(BasicListUI.java:2796)
	at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:290)
	at java.awt.Component.processMouseEvent(Component.java:6539)
	at javax.swing.JComponent.processMouseEvent(JComponent.java:3324)
	at java.awt.Component.processEvent(Component.java:6304)
	at java.awt.Container.processEvent(Container.java:2239)
	at java.awt.Component.dispatchEventImpl(Component.java:4889)
	at java.awt.Container.dispatchEventImpl(Container.java:2297)
	at java.awt.Component.dispatchEvent(Component.java:4711)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4904)
	at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4535)
	at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4476)
	at java.awt.Container.dispatchEventImpl(Container.java:2283)
	at java.awt.Window.dispatchEventImpl(Window.java:2746)
	at java.awt.Component.dispatchEvent(Component.java:4711)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:760)
	at java.awt.EventQueue.access$500(EventQueue.java:97)
	at java.awt.EventQueue$3.run(EventQueue.java:709)
	at java.awt.EventQueue$3.run(EventQueue.java:703)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:84)
	at java.awt.EventQueue$4.run(EventQueue.java:733)
	at java.awt.EventQueue$4.run(EventQueue.java:731)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:730)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
	at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
	at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)
Caused by: java.lang.NullPointerException
	at org.optaplanner.examples.conferencescheduling.solver.Rule_Talk_required_room_tags1103044632.defaultConsequence(Rule_Talk_required_room_tags1103044632.java:8)
	at org.optaplanner.examples.conferencescheduling.solver.Rule_Talk_required_room_tags1103044632DefaultConsequenceInvokerGenerated.evaluate(Unknown Source)
	at org.optaplanner.examples.conferencescheduling.solver.Rule_Talk_required_room_tags1103044632DefaultConsequenceInvoker.evaluate(Unknown Source)
	at org.drools.core.phreak.RuleExecutor.innerFireActivation(RuleExecutor.java:432)
	... 56 more