Javadoc As UML View

On my Eclipse Mars (4.5) installation on Windows 10, the plugin does not work. I found the following exception in the exclipse log:

java.lang.NullPointerException
at javadocasumlviewer.views.View$1.paintControl(View.java:967)
at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:230)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4362)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1113)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1137)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1122)
at org.eclipse.swt.widgets.Composite.WM_PAINT(Composite.java:1512)
at org.eclipse.swt.widgets.Control.windowProc(Control.java:4733)
at org.eclipse.swt.widgets.Canvas.windowProc(Canvas.java:339)
at org.eclipse.swt.widgets.Display.windowProc(Display.java:5063)
at org.eclipse.swt.internal.win32.OS.RedrawWindow(Native Method)
at org.eclipse.swt.widgets.Control.update(Control.java:4493)
at org.eclipse.swt.widgets.Control.update(Control.java:4483)
at org.eclipse.e4.ui.workbench.renderers.swt.SashLayout$2.mouseMove(SashLayout.java:111)
at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:212)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4362)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1113)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4180)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3769)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$4.run(PartRenderingEngine.java:1127)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:337)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1018)
at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:156)
at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:654)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:337)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:598)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:150)
at org.eclipse.ui.internal.ide.application.IDEApplication.start(IDEApplication.java:139)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:380)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:235)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:669)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:608)
at org.eclipse.equinox.launcher.Main.run(Main.java:1515)

Best regards
Ansgar

In schools in germany this tool is very useful, because in computer science one has to learn this kind of visualisation equals to a programming language.
For the IDE BlueJ there exists a similar extension.

Thank you for your tool that is fast and easy (for pupils) to use
Ulrich