Exception in thread "AWT-EventQueue-0" java.lang.IllegalArgumentException: The variableName (Computer) for entityClass (class org.optaplanner.examples.cloudbalancing.domain.CloudProcess) exists as a property (getter/setter) on that class, but not as an annotated as a planning variable.
Check if your planning entity's getter has the annotation PlanningVariable (or a shadow variable annotation).
	at org.optaplanner.core.impl.domain.solution.descriptor.SolutionDescriptor.findVariableDescriptorOrFail(SolutionDescriptor.java:759)
	at org.optaplanner.core.impl.score.director.AbstractScoreDirector.beforeVariableChanged(AbstractScoreDirector.java:287)
	at org.optaplanner.examples.cloudbalancing.optional.realtime.DeleteComputerProblemFactChange.doChange(DeleteComputerProblemFactChange.java:46)
	at org.optaplanner.examples.common.business.SolutionBusiness.doProblemFactChange(SolutionBusiness.java:306)
	at org.optaplanner.examples.common.swingui.SolutionPanel.doProblemFactChange(SolutionPanel.java:211)
	at org.optaplanner.examples.common.swingui.SolutionPanel.doProblemFactChange(SolutionPanel.java:207)
	at org.optaplanner.examples.cloudbalancing.swingui.CloudBalancingPanel.deleteComputer(CloudBalancingPanel.java:234)
	at org.optaplanner.examples.cloudbalancing.swingui.CloudComputerPanel.lambda$createTotalsUI$0(CloudComputerPanel.java:110)
	at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2022)
	at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2348)
	at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
	at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
	at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
	at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:289)
	at java.awt.Component.processMouseEvent(Component.java:6533)
	at javax.swing.JComponent.processMouseEvent(JComponent.java:3324)
	at java.awt.Component.processEvent(Component.java:6298)
	at java.awt.Container.processEvent(Container.java:2236)
	at java.awt.Component.dispatchEventImpl(Component.java:4889)
	at java.awt.Container.dispatchEventImpl(Container.java:2294)
	at java.awt.Component.dispatchEvent(Component.java:4711)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4888)
	at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4525)
	at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4466)
	at java.awt.Container.dispatchEventImpl(Container.java:2280)
	at java.awt.Window.dispatchEventImpl(Window.java:2746)
	at java.awt.Component.dispatchEvent(Component.java:4711)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
	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:76)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
	at java.awt.EventQueue$4.run(EventQueue.java:731)
	at java.awt.EventQueue$4.run(EventQueue.java:729)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
	at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
	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)