NoSuchMethodError at validator plugin

[Moonglum]

Path: trunk
URL: ​http://josm.openstreetmap.de/svn/trunk
Repository Root: ​http://josm.openstreetmap.de/svn
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
Revision: 1599
Node Kind: directory
Last Changed Author: framm
Last Changed Rev: 1599
Last Changed Date: 2009-05-19 00:16:01 +0200 (Tue, 19 May 2009)

Java version: 1.6.0_13
Plugins: editgpx;multipoly;routing;utilsplugin;validator;wmsplugin
Plugin editgpx Version: 14247
Plugin multipoly Version: ${version.entry.commit.revision}
Plugin routing Version: 14884
Plugin utilsplugin Version: 14356
Plugin validator Version: 14406
Plugin wmsplugin Version: 15091

java.lang.NoSuchMethodError: org.openstreetmap.josm.data.osm.Way.isClosed()Ljava/lang/Boolean;

at org.openstreetmap.josm.plugins.validator.tests.UnclosedWays.visit(UnclosedWays.java:105)
at org.openstreetmap.josm.data.osm.Way.visit(Way.java:66)
at org.openstreetmap.josm.plugins.validator.Test.visit(Test.java:127)
at org.openstreetmap.josm.plugins.validator.ValidateAction.doValidate(ValidateAction.java:90)
at org.openstreetmap.josm.plugins.validator.ValidateAction.actionPerformed(ValidateAction.java:45)
at org.openstreetmap.josm.plugins.validator.ValidatorDialog.actionPerformed(ValidatorDialog.java:305)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.AWTEventMulticaster.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(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.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(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.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)

Exception was thrown when I tried to validate manually
and also when I tried to upload data to OSM.

[Moonglum]

Closed as duplicate of #2610.