java.lang.ClassCastException when hitting the "w" button when drawing a line.

[rickmastfan67]

Just was normally editing tonight with the newest latest build and this error just popped up when I hit the "s" button while drawing a line.

Might be related to the [5358] fix, or I just somehow triggered something very rare.

Repository Root: http://josm.openstreetmap.de/svn
Build-Date: 2012-07-25 01:31:12
Last Changed Author: Don-vip
Revision: 5361
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
URL: http://josm.openstreetmap.de/svn/trunk
Last Changed Date: 2012-07-25 02:31:52 +0200 (Wed, 25 Jul 2012)
Last Changed Rev: 5361

Identification: JOSM/1.5 (5361 en)
Memory Usage: 122 MB / 2730 MB (41 MB allocated, but free)
Java version: 1.7.0_05, Oracle Corporation, Java HotSpot(TM) 64-Bit Server VM
Operating system: Windows 7
Dataset consistency test: No problems found

Plugin: OpeningHoursEditor (28477)
Plugin: buildings_tools (28412)
Plugin: mapdust (28412)
Plugin: measurement (28412)
Plugin: openstreetbugs (28412)
Plugin: reverter (28503)
Plugin: turnrestrictions (28412)
Plugin: undelete (28501)
Plugin: utilsplugin2 (28412)

java.lang.ClassCastException: org.openstreetmap.josm.tools.SubclassFilteredCollection cannot be cast to java.util.List
	at org.openstreetmap.josm.actions.mapmode.ImproveWayAccuracyAction.startImproving(ImproveWayAccuracyAction.java:589)
	at org.openstreetmap.josm.actions.mapmode.ImproveWayAccuracyAction.updateStateByCurrentSelection(ImproveWayAccuracyAction.java:629)
	at org.openstreetmap.josm.actions.mapmode.ImproveWayAccuracyAction.enterMode(ImproveWayAccuracyAction.java:139)
	at org.openstreetmap.josm.gui.MapFrame.selectMapMode(MapFrame.java:370)
	at org.openstreetmap.josm.gui.MapFrame.selectMapMode(MapFrame.java:349)
	at org.openstreetmap.josm.actions.mapmode.MapMode.actionPerformed(MapMode.java:74)
	at javax.swing.SwingUtilities.notifyAction(Unknown Source)
	at javax.swing.JComponent.processKeyBinding(Unknown Source)
	at javax.swing.KeyboardManager.fireBinding(Unknown Source)
	at javax.swing.KeyboardManager.fireKeyboardAction(Unknown Source)
	at javax.swing.JComponent.processKeyBindingsForAllComponents(Unknown Source)
	at javax.swing.JComponent.processKeyBindings(Unknown Source)
	at javax.swing.JComponent.processKeyEvent(Unknown Source)
	at java.awt.Component.processEvent(Unknown Source)
	at java.awt.Container.processEvent(Unknown Source)
	at java.awt.Component.dispatchEventImpl(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.KeyboardFocusManager.redispatchEvent(Unknown Source)
	at java.awt.DefaultKeyboardFocusManager.dispatchKeyEvent(Unknown Source)
	at java.awt.DefaultKeyboardFocusManager.preDispatchKeyEvent(Unknown Source)
	at java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(Unknown Source)
	at java.awt.DefaultKeyboardFocusManager.dispatchEvent(Unknown Source)
	at java.awt.Component.dispatchEventImpl(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Window.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
	at java.awt.EventQueue.access$000(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$1.doIntersectionPrivilege(Unknown Source)
	at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue$4.run(Unknown Source)
	at java.awt.EventQueue$4.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$1.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)

[akks]

It seems you have pressed W, not S :)
I confirm the bug, it is very simple to reproduce - press W while drawing line by A (more than 1 segment).

[Don-vip]

Certainly caused by my commit in r5360. Looks like ImproveWayAccuracyAction assumes DataSet.getSelection() returns a List instead of a Collection.

[Don-vip]

That's it: ​http://josm.openstreetmap.de/browser/josm/trunk/src/org/openstreetmap/josm/actions/mapmode/ImproveWayAccuracyAction.java#L589

I do not have SVN access right now, can someone remove this cast, use Collection and iterator().next() instead of get(0) ?
We need also to check if other classes made this (bad) assumption.

[rickmastfan67]

Fixed the subject. ;)

[akks]

I have searched through the core and found no more bad assumptions (no more unchecked conversions to types *List*<*> or List of selections).
Not so sure about plugins...

[akks]

In 5364/josm:

fix #7899 by Don-vip: exception hen hitting the "w" button when drawing a line.

[akks]

Please check the change and reopen if similar problem persists.

[Don-vip]

Looks fine :) Thank you !

[Don-vip]

Ticket #7901 has been marked as a duplicate of this ticket.