NPE on SE simple editor

gistfile1.txt

Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
        at org.orbisgis.legend.structure.stroke.constant.ConstantPenStrokeLegend.<init>(ConstantPenStrokeLegend.java:56)
        at org.orbisgis.legend.structure.graphic.ProportionalWKNLegend.<init>(ProportionalWKNLegend.java:59)
        at org.orbisgis.legend.thematic.proportional.ProportionalPoint.<init>(ProportionalPoint.java:78)
        at org.orbisgis.legend.analyzer.symbolizers.PointSymbolizerAnalyzer.analyze(PointSymbolizerAnalyzer.java:91)
        at org.orbisgis.legend.analyzer.symbolizers.PointSymbolizerAnalyzer.<init>(PointSymbolizerAnalyzer.java:62)
        at org.orbisgis.legend.thematic.factory.LegendFactory.getLegend(LegendFactory.java:69)
        at org.orbisgis.legend.thematic.factory.LegendFactory.getLegend(LegendFactory.java:57)
        at org.orbisgis.view.toc.actions.cui.LegendsPanel.init(LegendsPanel.java:126)
        at org.orbisgis.view.toc.Toc.onSimpleEditor(Toc.java:994)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:37)
        at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:244)
        at java.beans.EventHandler.invokeInternal(EventHandler.java:463)
        at java.beans.EventHandler.access$000(EventHandler.java:261)
        at java.beans.EventHandler$1.run(EventHandler.java:411)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.beans.EventHandler.invoke(EventHandler.java:409)
        at $Proxy1.actionPerformed(Unknown Source)
        at org.orbisgis.view.components.actions.DefaultAction.actionPerformed(DefaultAction.java:133)
        at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
        at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318)
        at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
        at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
        at javax.swing.AbstractButton.doClick(AbstractButton.java:357)
        at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:809)
        at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:850)
        at java.awt.AWTEventMulticaster.mouseReleased(AWTEventMulticaster.java:272)
        at java.awt.Component.processMouseEvent(Component.java:6297)
        at javax.swing.JComponent.processMouseEvent(JComponent.java:3275)
        at java.awt.Component.processEvent(Component.java:6062)
        at java.awt.Container.processEvent(Container.java:2039)
        at java.awt.Component.dispatchEventImpl(Component.java:4660)
        at java.awt.Container.dispatchEventImpl(Container.java:2097)
        at java.awt.Component.dispatchEvent(Component.java:4488)
        at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4575)
        at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4236)
        at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4166)
        at java.awt.Container.dispatchEventImpl(Container.java:2083)
        at java.awt.Window.dispatchEventImpl(Window.java:2489)
        at java.awt.Component.dispatchEvent(Component.java:4488)
        at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:668)
        at java.awt.EventQueue.access$400(EventQueue.java:81)
        at java.awt.EventQueue$2.run(EventQueue.java:627)
        at java.awt.EventQueue$2.run(EventQueue.java:625)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
        at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:98)
        at java.awt.EventQueue$3.run(EventQueue.java:641)
        at java.awt.EventQueue$3.run(EventQueue.java:639)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.security.AccessControlContext$1.doIntersectionPrivilege(AccessControlContext.java:87)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:638)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)