Attempt to use "Turn Lanes" plugin causes exception

[anonymous]

What steps will reproduce the problem?

1. Install "Turn Lanes" ("turnlanes") plugin (Not "turnlanes-tagging" and not "turnrestrictions")
2. Let JOSM restart
3. Click a junction (not sure if this is relevant)
4. Open Windows menu
5. Click "Turn Lanes"

What is the expected result?

Turn Lane windows should open

What happens instead?

"An unexpected exception occurred.
This is always a coding error. If you are running hte latest version of JOSM, please consider being kind and file a bug report.

Is JOSM up to date?

Your current version of JOSM is 12,039
JOSM is up to date."

Please provide any additional information below. Attach a screenshot if possible.

URL:http://josm.openstreetmap.de/svn/trunk
Repository:UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Last:Changed Date: 2017-05-02 23:28:33 +0200 (Tue, 02 May 2017)
Build-Date:2017-05-02 21:34:40
Revision:12039
Relative:URL: ^/trunk

Identification: JOSM/1.5 (12039 en_GB) Windows 7 64-Bit
Memory Usage: 456 MB / 907 MB (246 MB allocated, but free)
Java version: 1.8.0_131-b11, Oracle Corporation, Java HotSpot(TM) 64-Bit Server VM
Screen: \Display0 1920x1080, \Display1 1680x1050
Maximum Screen Size: 1920x1080
Program arguments: [org.openstreetmap.josm.Main]
Dataset consistency test: No problems found

Plugins:
+ turnlanes (33088)

Last errors/warnings:
- W: extended font config - overriding 'allfonts.symbol=Symbol' with 'Segoe UI Symbol'
- E: Handled by bug report queue: sun.dc.pr.PRError: setDashT4: invalid dash transformation (singular)
- E: Handled by bug report queue: sun.dc.pr.PRError: setDashT4: invalid dash transformation (singular)


=== REPORTED CRASH DATA ===
BugReportExceptionHandler#handleException:
No data collected.

Warning issued by: BugReportExceptionHandler#handleException

=== STACK TRACE ===
Thread: AWT-EventQueue-0 (20) of main
sun.dc.pr.PRError: setDashT4: invalid dash transformation (singular)
	at sun.dc.pr.PathDasher.setDashT4(Native Method)
	at sun.dc.pr.Rasterizer.setDashT4(Unknown Source)
	at sun.dc.DuctusRenderingEngine.getAATileGenerator(Unknown Source)
	at sun.java2d.pipe.AAShapePipe.renderPath(Unknown Source)
	at sun.java2d.pipe.AAShapePipe.draw(Unknown Source)
	at sun.java2d.pipe.PixelToParallelogramConverter.draw(Unknown Source)
	at sun.java2d.pipe.ValidatePipe.draw(Unknown Source)
	at sun.java2d.SunGraphics2D.draw(Unknown Source)
	at org.openstreetmap.josm.plugins.turnlanes.gui.RoadGui.paintLanes(RoadGui.java:735)
	at org.openstreetmap.josm.plugins.turnlanes.gui.RoadGui.paintLanes(RoadGui.java:666)
	at org.openstreetmap.josm.plugins.turnlanes.gui.RoadGui.paint(RoadGui.java:587)
	at org.openstreetmap.josm.plugins.turnlanes.gui.JunctionPane.paintPassive(JunctionPane.java:451)
	at org.openstreetmap.josm.plugins.turnlanes.gui.JunctionPane.paintComponent(JunctionPane.java:391)
	at javax.swing.JComponent.paint(Unknown Source)
	at javax.swing.JComponent.paintChildren(Unknown Source)
	at javax.swing.JComponent.paint(Unknown Source)
	at javax.swing.JComponent.paintChildren(Unknown Source)
	at javax.swing.JComponent.paint(Unknown Source)
	at javax.swing.JComponent.paintChildren(Unknown Source)
	at javax.swing.JComponent.paint(Unknown Source)
	at javax.swing.JComponent.paintChildren(Unknown Source)
	at org.openstreetmap.josm.gui.widgets.MultiSplitPane.paintChildren(MultiSplitPane.java:206)
	at javax.swing.JComponent.paint(Unknown Source)
	at javax.swing.JComponent.paintChildren(Unknown Source)
	at javax.swing.JComponent.paint(Unknown Source)
	at javax.swing.JComponent.paintChildren(Unknown Source)
	at javax.swing.JSplitPane.paintChildren(Unknown Source)
	at javax.swing.JComponent.paint(Unknown Source)
	at javax.swing.JComponent.paintChildren(Unknown Source)
	at javax.swing.JComponent.paint(Unknown Source)
	at javax.swing.JComponent.paintChildren(Unknown Source)
	at javax.swing.JComponent.paint(Unknown Source)
	at javax.swing.JComponent.paintChildren(Unknown Source)
	at javax.swing.JComponent.paint(Unknown Source)
	at javax.swing.JComponent.paintChildren(Unknown Source)
	at javax.swing.JComponent.paint(Unknown Source)
	at javax.swing.JLayeredPane.paint(Unknown Source)
	at javax.swing.JComponent.paintChildren(Unknown Source)
	at javax.swing.JComponent.paint(Unknown Source)
	at javax.swing.JComponent.paintToOffscreen(Unknown Source)
	at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(Unknown Source)
	at javax.swing.RepaintManager$PaintManager.paint(Unknown Source)
	at javax.swing.RepaintManager.paint(Unknown Source)
	at javax.swing.JComponent._paintImmediately(Unknown Source)
	at javax.swing.JComponent.paintImmediately(Unknown Source)
	at javax.swing.RepaintManager$4.run(Unknown Source)
	at javax.swing.RepaintManager$4.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
	at javax.swing.RepaintManager.paintDirtyRegions(Unknown Source)
	at javax.swing.RepaintManager.paintDirtyRegions(Unknown Source)
	at javax.swing.RepaintManager.prePaintDirtyRegions(Unknown Source)
	at javax.swing.RepaintManager.access$1200(Unknown Source)
	at javax.swing.RepaintManager$ProcessingRunnable.run(Unknown Source)
	at java.awt.event.InvocationEvent.dispatch(Unknown Source)
	at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
	at java.awt.EventQueue.access$500(Unknown Source)
	at java.awt.EventQueue$3.run(Unknown Source)
	at java.awt.EventQueue$3.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue.dispatchEvent(Unknown Source)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.run(Unknown Source)

[hamish.blair@…]

point at which turn lanes window failed to get created

[Hamish Blair <hamish.blair@…>]

Restarted, in cygwin (java -jar josm-tested.jar), didn't click anything on the map, just opened Windows menu, then selected Turn Lanes, minimised other windows, couldn't find Turn Lanes window. Retried opening Windows menu, clicked Turn Lanes again, then window appeared.
Closed JOSM

Opened JOSM from Windows cmd: java -jar josm-tested.jar org.openstreetmap.josm.Main
Turn Lanes window was still open.

Exception must have been because I selected a junction before I opened the Turn Lanes window.