JOSM breaks when monitor attached/detached

[me@…]

What steps will reproduce the problem?

1. Run josm
2. Detach/attach monitor (it's lenovo t430s, so in fact dock/undock)
3. Touch something on UI
4. See endless loop of errors coming out

What is the expected result?

Everything works.

What happens instead?

I have to kill josm, which is problematic since error messages keep stealing focus

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: 2016-02-11 01:14:54 +0100 (Thu, 11 Feb 2016)
Build-Date:2016-02-11 02:32:48
Revision:9784
Relative:URL: ^/trunk

Identification: JOSM/1.5 (9784 be) Linux Ubuntu Xenial Xerus (development branch)
Memory Usage: 991 MB / 991 MB (911 MB allocated, but free)
Java version: 1.8.0_72-b15, Oracle Corporation, Java HotSpot(TM) 64-Bit Server VM
VM arguments: [-Djava.net.preferIPv4Stack=true]

Plugins:
- FastDraw (31895)
- Mapillary (32040)
- OpeningHoursEditor (31772)
- apache-commons (31895)
- apache-http (31895)
- buildings_tools (31895)
- imagery_offset_db (32046)
- reverter (32005)

Last errors/warnings:
- E: java.lang.ClassCastException: sun.awt.image.BufImgSurfaceData cannot be cast to sun.java2d.xr.XRSurfaceData
- E: java.lang.ClassCastException: sun.awt.image.BufImgSurfaceData cannot be cast to sun.java2d.xr.XRSurfaceData
- E: java.lang.ClassCastException: sun.awt.image.BufImgSurfaceData cannot be cast to sun.java2d.xr.XRSurfaceData
- E: java.lang.ClassCastException: sun.awt.image.BufImgSurfaceData cannot be cast to sun.java2d.xr.XRSurfaceData
- E: java.lang.ClassCastException: sun.awt.image.BufImgSurfaceData cannot be cast to sun.java2d.xr.XRSurfaceData

java.lang.ClassCastException: sun.awt.image.BufImgSurfaceData cannot be cast to sun.java2d.xr.XRSurfaceData
	at sun.java2d.xr.XRPMBlitLoops.cacheToTmpSurface(XRPMBlitLoops.java:145)
	at sun.java2d.xr.XrSwToPMBlit.Blit(XRPMBlitLoops.java:353)
	at sun.java2d.SurfaceDataProxy.updateSurfaceData(SurfaceDataProxy.java:498)
	at sun.java2d.SurfaceDataProxy.replaceData(SurfaceDataProxy.java:455)
	at sun.java2d.SurfaceData.getSourceSurfaceData(SurfaceData.java:233)
	at sun.java2d.pipe.DrawImage.renderImageCopy(DrawImage.java:566)
	at sun.java2d.pipe.DrawImage.copyImage(DrawImage.java:67)
	at sun.java2d.pipe.DrawImage.copyImage(DrawImage.java:1014)
	at sun.java2d.SunGraphics2D.drawImage(SunGraphics2D.java:3318)
	at sun.awt.image.ImageRepresentation.drawToBufImage(ImageRepresentation.java:813)
	at sun.java2d.pipe.DrawImage.copyImage(DrawImage.java:1021)
	at sun.java2d.pipe.ValidatePipe.copyImage(ValidatePipe.java:186)
	at sun.java2d.SunGraphics2D.drawImage(SunGraphics2D.java:3318)
	at sun.java2d.SunGraphics2D.drawImage(SunGraphics2D.java:3296)
	at javax.swing.ImageIcon.paintIcon(ImageIcon.java:425)
	at javax.swing.plaf.basic.BasicLabelUI.paint(BasicLabelUI.java:167)
	at javax.swing.plaf.ComponentUI.update(ComponentUI.java:161)
	at javax.swing.JComponent.paintComponent(JComponent.java:780)
	at javax.swing.JComponent.paint(JComponent.java:1056)
	at javax.swing.JComponent.paintChildren(JComponent.java:889)
	at javax.swing.JComponent.paint(JComponent.java:1065)
	at javax.swing.JComponent.paintChildren(JComponent.java:889)
	at javax.swing.JComponent.paint(JComponent.java:1065)
	at javax.swing.JViewport.paint(JViewport.java:728)
	at javax.swing.JComponent.paintChildren(JComponent.java:889)
	at javax.swing.JComponent.paint(JComponent.java:1065)
	at javax.swing.JComponent.paintChildren(JComponent.java:889)
	at javax.swing.JComponent.paint(JComponent.java:1065)
	at javax.swing.JLayeredPane.paint(JLayeredPane.java:586)
	at javax.swing.JComponent.paintChildren(JComponent.java:889)
	at javax.swing.JComponent.paintToOffscreen(JComponent.java:5217)
	at javax.swing.RepaintManager$PaintManager.paintDoubleBuffered(RepaintManager.java:1579)
	at javax.swing.RepaintManager$PaintManager.paint(RepaintManager.java:1502)
	at javax.swing.RepaintManager.paint(RepaintManager.java:1272)
	at javax.swing.JComponent.paint(JComponent.java:1042)
	at java.awt.GraphicsCallback$PaintCallback.run(GraphicsCallback.java:39)
	at sun.awt.SunGraphicsCallback.runOneComponent(SunGraphicsCallback.java:79)
	at sun.awt.SunGraphicsCallback.runComponents(SunGraphicsCallback.java:116)
	at java.awt.Container.paint(Container.java:1975)
	at java.awt.Window.paint(Window.java:3912)
	at javax.swing.RepaintManager$4.run(RepaintManager.java:842)
	at javax.swing.RepaintManager$4.run(RepaintManager.java:814)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
	at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:814)
	at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:789)
	at javax.swing.RepaintManager.prePaintDirtyRegions(RepaintManager.java:738)
	at javax.swing.RepaintManager.access$1200(RepaintManager.java:64)
	at javax.swing.RepaintManager$ProcessingRunnable.run(RepaintManager.java:1732)
	at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311)
	at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:756)
	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.awt.EventQueue.dispatchEvent(EventQueue.java:726)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
	at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:109)
	at java.awt.WaitDispatchSupport$2.run(WaitDispatchSupport.java:184)
	at java.awt.WaitDispatchSupport$4.run(WaitDispatchSupport.java:229)
	at java.awt.WaitDispatchSupport$4.run(WaitDispatchSupport.java:227)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.awt.WaitDispatchSupport.enter(WaitDispatchSupport.java:227)
	at java.awt.Dialog.show(Dialog.java:1084)
	at java.awt.Component.show(Component.java:1673)
	at java.awt.Component.setVisible(Component.java:1625)
	at java.awt.Window.setVisible(Window.java:1014)
	at java.awt.Dialog.setVisible(Dialog.java:1005)
...<snip>...

[bastiK]

This is a ​java bug, I don't think we can do anything about it.

[Don-vip]

Document it and contact Oracle if we can, see #11620 #11385 #11002 and JavaBugs.