Cycle detected in graph

[johardi]

Uncaught Exception in thread 'AWT-EventQueue-0'
java.lang.RuntimeException: Cycle detected in graph
    at org.eclipse.draw2d.graph.InitialRankSolver.solve(InitialRankSolver.java:54) ~[na:na]
    at org.eclipse.draw2d.graph.InitialRankSolver.visit(InitialRankSolver.java:33) ~[na:na]
    at org.eclipse.draw2d.graph.DirectedGraphLayout.visit(DirectedGraphLayout.java:98) ~[na:na]
    at org.eclipse.zest.layouts.algorithms.DirectedGraphLayoutAlgorithm$ExtendedDirectedGraphLayout.visit(DirectedGraphLayoutAlgorithm.java:43) ~[na:na]
    at org.eclipse.zest.layouts.algorithms.DirectedGraphLayoutAlgorithm.applyLayoutInternal(DirectedGraphLayoutAlgorithm.java:83) ~[na:na]
    at org.eclipse.zest.layouts.algorithms.AbstractLayoutAlgorithm.applyLayout(AbstractLayoutAlgorithm.java:481) ~[na:na]
    at ca.uvic.cs.chisel.cajun.actions.LayoutAction.runLayout(LayoutAction.java:121) ~[na:na]
    at ca.uvic.cs.chisel.cajun.actions.LayoutAction.doAction(LayoutAction.java:79) ~[na:na]
    at ca.uvic.cs.chisel.cajun.actions.CajunAction.actionPerformed(CajunAction.java:57) ~[na:na]
    at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2022) ~[na:1.8.0_51]
    at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2346) ~[na:1.8.0_51]
    at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402) ~[na:1.8.0_51]
    at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259) ~[na:1.8.0_51]
    at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252) ~[na:1.8.0_51]
    at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:289) ~[na:1.8.0_51]
    at java.awt.Component.processMouseEvent(Component.java:6525) ~[na:1.8.0_51]
    at javax.swing.JComponent.processMouseEvent(JComponent.java:3324) ~[na:1.8.0_51]
    at java.awt.Component.processEvent(Component.java:6290) ~[na:1.8.0_51]
    at java.awt.Container.processEvent(Container.java:2234) ~[na:1.8.0_51]
    at java.awt.Component.dispatchEventImpl(Component.java:4881) ~[na:1.8.0_51]
    at java.awt.Container.dispatchEventImpl(Container.java:2292) ~[na:1.8.0_51]
    at java.awt.Component.dispatchEvent(Component.java:4703) ~[na:1.8.0_51]
    at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4898) ~[na:1.8.0_51]
    at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4533) ~[na:1.8.0_51]
    at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4462) ~[na:1.8.0_51]
    at java.awt.Container.dispatchEventImpl(Container.java:2278) ~[na:1.8.0_51]
    at java.awt.Window.dispatchEventImpl(Window.java:2750) ~[na:1.8.0_51]
    at java.awt.Component.dispatchEvent(Component.java:4703) ~[na:1.8.0_51]
    at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758) ~[na:1.8.0_51]
    at java.awt.EventQueue.access$500(EventQueue.java:97) ~[na:1.8.0_51]
    at java.awt.EventQueue$3.run(EventQueue.java:709) ~[na:1.8.0_51]
    at java.awt.EventQueue$3.run(EventQueue.java:703) ~[na:1.8.0_51]
    at java.security.AccessController.doPrivileged(Native Method) ~[na:1.8.0_51]
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:75) ~[na:1.8.0_51]
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:86) ~[na:1.8.0_51]
    at java.awt.EventQueue$4.run(EventQueue.java:731) ~[na:1.8.0_51]
    at java.awt.EventQueue$4.run(EventQueue.java:729) ~[na:1.8.0_51]
    at java.security.AccessController.doPrivileged(Native Method) ~[na:1.8.0_51]
    at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:75) ~[na:1.8.0_51]
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:728) ~[na:1.8.0_51]
    at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201) [na:1.8.0_51]
    at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116) [na:1.8.0_51]
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105) [na:1.8.0_51]
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101) [na:1.8.0_51]
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93) [na:1.8.0_51]
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:82) [na:1.8.0_51]